The work done on the gas is -36 J and the change in internal energy of the gas is -64 J.
To determine the work done on the gas and the change in internal energy, we can use the first law of thermodynamics, which states that the change in internal energy of a system is equal to the heat added to the system minus the work done by the system:
ΔU = Q - W
Q = -100 J (negative since heat is removed)
P = 6 Pa
A₁ = 8 m²
A₂ = 2 m²
First, we need to calculate the change in volume (ΔV) using the formula for the change in volume of a gas undergoing a process with constant pressure:
ΔV = A₂ - A₁
ΔV = 2 m² - 8 m² = -6 m² (negative since the gas is being compressed)
Now, let's calculate the work done on the gas (W) using the formula:
W = PΔV
W = 6 Pa * (-6 m²) = -36 J (negative since work is done on the gas)
Next, we can determine the change in internal energy (ΔU) using the first law of thermodynamics:
ΔU = Q - W
ΔU = -100 J - (-36 J) = -100 J + 36 J = -64 J (negative since the internal energy decreases)
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Score 2 SA biker and her bike have a combined mass of 80.0 kg and are traveling at a speed of 3.00 m/s. If the same biker and bike travel twice as fast, their kinetic energy will_by a factor of Increa
The kinetic energy of the SA biker and her bike is increased by a factor of four (1440/360 = 4) when their velocity is doubled is the answer.
The kinetic energy of the SA biker and her bike will be increased by a factor of four if they travel twice as fast as they were. Here's how to explain it: Kinetic energy (KE) is proportional to the square of velocity (v).
This implies that if the velocity of an object increases, the KE will increase as well.
The formula for kinetic energy is: KE = 0.5mv²where KE = kinetic energy, m = mass, and v = velocity.
The SA biker and her bike have a combined mass of 80.0 kg and are travelling at a speed of 3.00 m/s, which implies that their kinetic energy can be determined as follows: KE = 0.5 x 80.0 x (3.00)²KE = 360 J
If the same biker and bike travel twice as fast, their velocity would be 6.00 m/s.
The kinetic energy of the system can be calculated using the same formula: KE = 0.5 x 80.0 x (6.00)²KE = 1440 J
The kinetic energy of the SA biker and her bike is increased by a factor of four (1440/360 = 4) when their velocity is doubled.
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A solid conducting sphere of radius 5 cm has a charge of 60 nc distributed uniformly over its surface Let S be a point on the surface of the sphere, and B be a point 10 cm from the center of the sphere what is the electric Potential difference between Points S and B Vs-VB
The electric potential difference between points S and B is 16.182 volts.
To find the electric potential difference (ΔV) between points S and B, we can use the formula:
ΔV = k * (Q / rS) - k * (Q / rB)
where:
- ΔV is the electric potential difference
- k is the electrostatic constant (k = 8.99 *[tex]10^9[/tex] N m²/C²)
- Q is the charge on the sphere (Q = 60 nC = 60 * [tex]10^{-9[/tex] C)
- rS is the distance between point S and the center of the sphere (rS = 5 cm = 0.05 m)
- rB is the distance between point B and the center of the sphere (rB = 10 cm = 0.1 m)
Plugging in the values, we get:
ΔV = (8.99 *[tex]10^9[/tex] N m²/C²) * (60* [tex]10^{-9[/tex] C / 0.05 m) - (8.99 *[tex]10^9[/tex] N m²/C²) * (60 * [tex]10^{-9[/tex] C/ 0.1 m)
Simplifying the equation:
ΔV = (8.99 *[tex]10^9[/tex] N m²/C²) * (1.2 * 10^-7 C / 0.05 m) - (8.99 *[tex]10^9[/tex] N m²/C²) * (6 *[tex]10^{-8[/tex] C / 0.1 m)
Calculating further:
ΔV = (8.99*[tex]10^9[/tex] N m²/C²) * (2.4 *[tex]10^{-6[/tex]C/m) - (8.99 *[tex]10^9[/tex] Nm²/C²) * (6 * [tex]10^{-7[/tex] C/m)
Simplifying and subtracting:
ΔV = (8.99*[tex]10^9[/tex] N m²/C²) * (1.8 *[tex]10^{-6[/tex] C/m)
Evaluating the expression:
ΔV = 16.182 V
Therefore, the electric potential difference between points S and B is 16.182 volts.
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A voltage source E-5V is connected in series to a capacitance of 1 x 10 farad and a resistance of 4 ohms. What is the appropriate equation to model the behavior of the charge. Q. 100+ 4Q = 5 4 + 10 "Q-5 540 +10°Q = 4 de 04+109Q = 5 dr
The appropriate equation to model the behavior of the charge is Q - 5 + 10⁹Q = 4.
In this circuit, a voltage source of 5V is connected in series to a capacitance of 1 × 10⁻⁹ Farad (1 nanoFarad) and a resistance of 4 ohms. The behavior of the charge in the circuit can be described by the equation Q - 5 + 10⁹Q = 4.
Let's break down the equation:
Q represents the charge in Coulombs on the capacitor.
The first term, Q, accounts for the charge stored on the capacitor.
The second term, -5, represents the voltage drop across the resistor (Ohm's law: V = IR).
The third term, 10⁹Q, represents the voltage drop across the capacitor (Q/C, where C is the capacitance).
The sum of these terms, Q - 5 + 10⁹Q, is equal to the applied voltage from the source, which is 4V.
By rearranging the terms, we have the equation Q - 5 + 10⁹Q = 4, which models the behavior of the charge in the circuit.
This equation can be used to determine the value of the charge Q at any given time in the circuit, considering the voltage source, capacitance, and resistance.
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A 5.24-kg bowling ball moving at 8.95 m/s collides with a 0.811-kg bowling pin, which is scattered at
an angle of 82.6 to the initial direction of the bowling ball and with a speed of 13.2 m/s.
Calculate the final velocity (magnitude and direction) of the bowling ball. (remember to enter the
correct sign for the angle).
The final velocity of the bowling ball is 6.05 m/s at an angle of 42.6 degrees to its original direction.
Using the principle of conservation of momentum, we can calculate the final velocity of the bowling ball. The initial momentum of the system is the sum of the momentum of the bowling ball and bowling pin, which is equal to the final momentum of the system.
P(initial) = P(final)
m1v1 + m2v2 = (m1 + m2)vf
where m1 = 5.24 kg, v1 = 8.95 m/s,
m2 = 0.811 kg, v2 = 13.2 m/s,
and vf is the final velocity of the bowling ball.
Solving for vf, we get:
vf = (m1v1 + m2v2)/(m1 + m2)
vf = (5.24 kg x 8.95 m/s + 0.811 kg x 13.2 m/s)/(5.24 kg + 0.811 kg)
vf = 6.05 m/s
To find the angle, we can use trigonometry.
tan θ = opposite/adjacent
tan θ = (vfy/vfx)
θ = tan^-1(vfy/vfx)
where vfx and vfy are the x and y components of the final velocity.
vfx = vf cos(82.6)
vfy = vf sin(82.6)
θ = tan^-1((vfy)/(vfx))
θ = tan^-1((6.05 m/s sin(82.6))/ (6.05 m/s cos(82.6)))
θ = 42.6 degrees (rounded to one decimal place)
Therefore, the final velocity of the bowling ball is 6.05 m/s at an angle of 42.6 degrees to its original direction.
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Two charges are located on the x axis: 91 = +4.9 µC at x₁ = +4.9 cm, and q2 = +4.9 μC at x2 = -4.9 cm. Two other charges are located on the y axis: 93 +3.6 μC at y3 = +5.4 cm, and 94 = -11 μC at y4=+7.0 cm. Find (a) the magnitude and (b) the direction of the net electric field at the origin.
(a) The magnitude of the net electric field at the origin is approximately 1.32 x 10^6 N/C.(b) The direction of the net electric field at the origin is towards the negative x-axis.
To find the net electric field at the origin, we need to calculate the electric field contributions from each of the charges and then add them vectorially. The electric field due to a point charge is given by Coulomb's Law:
E = k * (q / r^2)
where E is the electric field, k is the electrostatic constant (k = 8.99 x 10^9 N m^2/C^2), q is the charge, and r is the distance between the charge and the point where the electric field is being calculated.Let's calculate the electric field contributions from each charge and then combine them:
Charge 1 (q1 = +4.9 µC) at x1 = +4.9 cm:
r1 = √((0 - x1)^2) = √((0 - 4.9 cm)^2) = 4.9 cm = 0.049 m
E1 = k * (q1 / r1^2) = (8.99 x 10^9 N m^2/C^2) * (4.9 x 10^-6 C / (0.049 m)^2) = 898000 N/C
Charge 2 (q2 = +4.9 µC) at x2 = -4.9 cm:
r2 = √((0 - x2)^2) = √((0 + 4.9 cm)^2) = 4.9 cm = 0.049 m
E2 = k * (q2 / r2^2) = (8.99 x 10^9 N m^2/C^2) * (4.9 x 10^-6 C / (0.049 m)^2) = 898000 N/C
Charge 3 (q3 = +3.6 µC) at y3 = +5.4 cm:
r3 = √((0 - y3)^2) = √((0 - 5.4 cm)^2) = 5.4 cm = 0.054 m
E3 = k * (q3 / r3^2) = (8.99 x 10^9 N m^2/C^2) * (3.6 x 10^-6 C / (0.054 m)^2) = 148000 N/C
Charge 4 (q4 = -11 µC) at y4 = +7.0 cm:
r4 = √((0 - y4)^2) = √((0 - 7.0 cm)^2) = 7.0 cm = 0.07 m
E4 = k * (q4 / r4^2) = (8.99 x 10^9 N m^2/C^2) * (-11 x 10^-6 C / (0.07 m)^2) = -170000 N/C
Now, we can add the electric fields vectorially. Since the electric field is a vector, we need to consider both magnitude and direction.
Magnitude of the net electric field:
|E_net| = √(E1^2 + E2^2 + E3^2 + E4^2)
|E_net| = √((898000 N/C)^2 + (898000 N/C)^2 + (148000 N/C)^2 + (-170000 N/C)^2)
|E_net| ≈ 1.32 x 10^6 N/C
Direction of the net electric field:
The direction of the net electric field can be determined by considering the x and y components of the individual electric fields.
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An
object is located at the focal point of a diverging lens. The image
is located at:
a. 3f/2
b. -f
c. At infinity
d. f
e. f/2
The image formed by a diverging lens when an object is located at its focal point is located at infinity.
When an object is located at the focal point of a diverging lens, the rays of light that pass through the lens emerge as parallel rays. This is because the diverging lens causes the light rays to spread out. Parallel rays of light are defined to be those that appear to originate from a point at infinity.
Since the rays of light are effectively parallel after passing through the diverging lens, they do not converge or diverge further to form a real image on any physical surface. Instead, the rays appear to come from a point at infinity, and this is where the virtual image is formed.
Therefore, the correct answer is c. At infinity.
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An initially-stationary electric dipole of dipole moment □=(5.00×10−10C⋅m)1 placed in an electric field □=(2.00×106 N/C) I+(2.00×106 N/C)j. What is the magnitude of the maximum torque that the electric field exerts on the dipole in units of 10−3 Nnm ? 1.40 2.80 0.00 1.00
The magnitude of the maximum torque that the electric field exerts on the dipole is[tex]1.00×10^-3[/tex]N⋅m, which is equivalent to 1.00 N⋅mm or [tex]1.00×10^-3[/tex] N⋅m.
The torque (τ) exerted on an electric dipole in an electric field is given by the formula:
τ = p * E * sin(θ)
where p is the dipole moment, E is the electric field, and θ is the angle between the dipole moment and the electric field.
In this case, the dipole moment is given as p = 5.00×[tex]10^-10[/tex] C⋅m, and the electric field is given as E = (2.00×1[tex]0^6[/tex] N/C) I + (2.00×[tex]10^6[/tex] N/C) j.
To find the magnitude of the maximum torque, we need to determine the angle θ between the dipole moment and the electric field.
Since the electric field is given in terms of its x- and y-components, we can calculate the angle using the formula:
θ = arctan(E_y / E_x)
Substituting the given values, we have:
θ = arctan((2.00×[tex]10^6[/tex] N/C) / (2.00×[tex]10^6[/tex] N/C)) = arctan(1) = π/4
Now we can calculate the torque:
τ = p* E * sin(θ) = (5.00×[tex]10^-10[/tex]C⋅m) * (2.00×[tex]10^6[/tex] N/C) * sin(π/4) = (5.00×[tex]10^-10[/tex] C⋅m) * (2.00×[tex]10^6[/tex] N/C) * (1/√2) = 1.00×[tex]10^-3[/tex]N⋅m
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Complete question
An initially-stationary electric dipole of dipole moment □=(5.00×10−10C⋅m)1 placed in an electric field □=(2.00×106 N/C) I+(2.00×106 N/C)j. What is the magnitude of the maximum torque that the electric field exerts on the dipole in units of 10−3 Nnm ?
How much work must be done by frictional forces in slowing a 1000-kg car from 25.3 m/s to rest? 3.2 × 105 J X 4,48 x 105 3.84 x *105J O 2.56 × 105 J
The work done by frictional forces in slowing the car from 25.3 m/s to rest is approximately -3.22 × 10^5 J.
To calculate the work done by frictional forces in slowing down the car, we need to use the work-energy principle, which states that the work done on an object is equal to the change in its kinetic energy.
The initial kinetic energy of the car is given by:
KE_initial = 1/2 * mass * (velocity_initial)^2
The final kinetic energy of the car is zero since it comes to rest:
KE_final = 0
The work done by frictional forces is equal to the change in kinetic energy:
Work = KE_final - KE_initial
Given:
Mass of the car = 1000 kg
Initial velocity = 25.3 m/s
Final velocity (rest) = 0
Plugging these values into the equation, we get:
Work = 0 - (1/2 * 1000 kg * (25.3 m/s)^2)
Calculating this expression, we find:
Work ≈ -3.22 × 10^5 J
The negative sign indicates that work is done against the motion of the car, which is consistent with the concept of frictional forces opposing the car's motion.
Therefore, the work done by frictional forces in slowing the car from 25.3 m/s to rest is approximately -3.22 × 10^5 J.
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Consider a cube whose volume is 125 cm3. Inside there are two point charges q1 = -24 pico and q2 = 9 pico. The flux of the electric field across the surface of the cube is: a.-5.5N/A b.1.02 N/A c.2.71 N/A d.-1.69 N/A
The flux of the electric-field across the surface of the cube is approximately -1.69 N/A.
To calculate the flux of the electric field, we can use Gauss's-Law, which states that the flux (Φ) of an electric field through a closed surface is equal to the enclosed charge (Q) divided by the permittivity of free space (ε₀). Since we have two point charges inside the cube, we need to calculate the total charge enclosed within the cube. Let's denote the volume charge density as ρ, and the volume of the cube as V.
The total charge enclosed is given by Q = ∫ρ dV, where we integrate over the volume of the cube.
Given that the volume of the cube is 125 cm³ and the point charges are located inside, we can find the flux of the electric field.
Using the formula Φ = Q / ε₀, we can calculate the flux.
Comparing the options given, we find that option d, -1.69 N/A, is the closest value to the calculated flux.
Therefore, the flux of the electric field across the surface of the cube is approximately -1.69 N/A.
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using dimensional anylsis, explain how to get the result to this question
Which is larger, 100,000 cm^3 or 1m^ Explain your answer.
Comparing this result to 1 m³, we can conclude that 1 m³ is larger than 100,000 cm³.
To determine which is larger between 100,000 cm³ and 1 m³, we can use dimensional analysis to compare the two quantities.
First, let's establish the conversion factor between centimeters and meters. There are 100 centimeters in 1 meter, so we can write the conversion factor as:
1 m = 100 cm
Now, let's convert the volume of 100,000 cm³ to cubic meters:
100,000 cm³ * (1 m / 100 cm)³
Simplifying the expression:
100,000 cm³ * (1/100)³ m³
100,000 cm³ * (1/1,000,000) m³
100,000 cm³ * 0.000001 m³
0.1 m³
Therefore, 100,000 cm³ is equal to 0.1 m³.
Comparing this result to 1 m³, we can conclude that 1 m³ is larger than 100,000 cm³.
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ertically polarized light of intensity l, is incident on a polarizer whose transmission axis is at an angle of 70° with the vertical. If the intensity of the transmitted light is measured to be 0.34W/m2, the intensity lo of the incident light is O 0.99 W/m2 O 0.43 W/m2 O 1.71 W/m2 O 2.91 W/m2
The intensity lo of the incident light is determined to be 1.71 W/m2. So, the correct option is c.
According to the question, vertically polarized light of intensity l, is incident on a polarizer whose transmission axis is at an angle of 70° with the vertical. If the intensity of the transmitted light is measured to be 0.34 W/m2, the intensity lo of the incident light can be calculated as follows:
Given, Intensity of transmitted light, I = 0.34 W/m²
Intensity of incident light, I₀ = ?
We know that the intensity of the transmitted light is given by:
I = I₀cos²θ
Where θ is the angle between the polarization direction of the incident light and the transmission axis of the polarizer.
So, by substituting the given values in the above equation, we have:
I₀ = I/cos²θ = 0.34/cos²70°≈1.71 W/m²
Therefore, the intensity lo of the incident light is 1.71 W/m2.
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How many lines per centimeter are there on a diffraction grating that gives a first-order maximum for 460-nm blue light at an angle of 17 deg? Hint The diffraction grating should have lines per centim
The diffraction grating that gives a first-order maximum for 460 nm blue light at an angle of 17 degrees should have approximately 0.640 lines per millimeter.
The formula to find the distance between two adjacent lines in a diffraction grating is:
d sin θ = mλ
where: d is the distance between adjacent lines in a diffraction gratingθ is the angle of diffraction
m is an integer that is the order of the diffraction maximumλ is the wavelength of the light
For first-order maximum,
m = 1λ = 460 nmθ = 17°
Substituting these values in the above formula gives:
d sin 17° = 1 × 460 nm
d sin 17° = 0.15625
The grating should have lines per centimeter. We can convert this to lines per millimeter by dividing by 10, i.e., multiplying by 0.1.
d = 0.1/0.15625
d = 0.640 lines per millimeter (approx)
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A 1350 kg car is going at a constant speed 55.0 km/h when it
turns through a radius of 210 m. How big is the centripetal force?
Answer in 'kiloNewtons'.
A 1350 kg car is going at a constant speed 55.0 km/h, the centripetal force exerted by the car on taking the turn is approximately 109.37 kN.
Given data
Mass of the car, m = 1350 kg
Speed of the car, v = 55.0 km/h = 15.28 m/s
Radius of the turn, r = 210 m
Formula to find centripetal force : F = (mv²)/r where,
m = mass of the object
v = velocity of the object
r = radius of the turn
The formula to calculate the centripetal force is given as : F = (mv²)/r
We know that, m = 1350 kg ; v = 15.28 m/s and r = 210 m
Substitute the given values in the above equation to get the centripetal force.
F = (1350 kg) × (15.28 m/s)² / 210 m≈ 109.37 kN
Thus, the centripetal force exerted by the car on taking the turn is approximately 109.37 kN.
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Astronomers measure the distance to a particular star to
be 6.0 light-years (1 ly = distance light travels in 1 year). A spaceship travels from Earth to the vicinity of this star at steady speed, arriving in 3.50 years as measured by clocks on the spaceship. (a) How long does the trip take as measured by clocks in Earth's reference frame? (b) What distance does the spaceship travel as measured in its own
reference frame?
The time taken by the spaceship as measured by Earth's reference frame can be calculated as follows: Δt′=Δt×(1−v2/c2)−1/2 where:v is the speed of the spaceship as measured in Earth's reference frame, c is the speed of lightΔt is the time taken by the spaceship as measured in its own reference frame.
The value of v is calculated as follows: v=d/Δt′where:d is the distance between Earth and the star, which is 6.0 light-years. Δt′ is the time taken by the spaceship as measured by Earth's reference frame.Δt is given as 3.50 years.Substituting these values, we get :v = d/Δt′=6.0/3.50 = 1.71 ly/yr.
Using this value of v in the first equation v is speed, we can find Δt′:Δt′=Δt×(1−v2/c2)−1/2=3.50×(1−(1.71)2/c2)−1/2=3.50×(1−(1.71)2/1)−1/2=2.42 years. Therefore, the trip takes 2.42 years as measured by clocks in Earth's reference frame.
The distance traveled by the spaceship as measured in its own reference frame is equal to the distance between Earth and the star, which is 6.0 light-years. This is because the spaceship is at rest in its own reference frame, so it measures the distance to the star to be the same as the distance measured by Earth astronomers.
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Hoover Dam on the Colorado River is the highest dam in the United States at 221 m, with an output of 1300MW. The dam generates electricity with water taken from a depth of 151 m and an average flow rate of 620 m 3
/s. (a) Calculate the power in this flow. Report your answer in Megawatts 1,000,000 W =1MW 25. Hoover Dam on the Colorado River is the highest dam in the United States at 221 m, with an output of 1300MW. The dam generates electricity with water taken from a depth of 150 m and an average flow rate of 650 m 3
/s. (a) Calculate the power in this flow. (b) What is the ratio of this power to the facility's average of 680 MW? (These are the same values as the regular homework assignment) The ratio is 2.12 The ratio is 1.41 The ratio is 0.71 The ratio is 0.47
Hoover Dam on the Colorado River is the tallest dam in the United States, measuring 221 meters in height, with an output of 1300MW. The dam's electricity is generated by water that is taken from a depth of 151 meters and flows at an average rate of 620 m3/s.Therefore, the correct answer is the ratio is 1.41.
To compute the power in this flow, we use the formula:Power = (density) * (Volume flow rate) * (acceleration due to gravity) * (head). Where density is the density of water, which is 1000 kg/m3, and the acceleration due to gravity is 9.81 m/s2. Head = (depth) * (density) * (acceleration due to gravity). Substituting these values,Power = (1000 kg/m3) * (620 m3/s) * (9.81 m/s2) * (151 m) = 935929200 Watts. Converting this value to Megawatts,Power in Megawatts = 935929200 / 1000000 = 935.93 MWFor the second question,
(a) The power in the second flow is given by the formula:Power = (density) * (Volume flow rate) * (acceleration due to gravity) * (head)Where density is the density of water, which is 1000 kg/m3, and the acceleration due to gravity is 9.81 m/s2.Head = (depth) * (density) * (acceleration due to gravity) Power = (1000 kg/m3) * (650 m3/s) * (9.81 m/s2) * (150 m) = 956439000 Watts. Converting this value to Megawatts,Power in Megawatts = 956439000 / 1000000 = 956.44 MW
(b) The ratio of the power in this flow to the facility's average power is given by:Ratio of the power = Power in the second flow / Average facility power= 956.44 MW / 680 MW= 1.41. Therefore, the correct answer is the ratio is 1.41.
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A
20-g cylinder of radius 5.0 cm starts to rotate from rest, reaching
200 rpm in half a minute. Find the net torque acting on the
cylinder.
The net torque acting on the cylinder is approximately 0.031 N·m.
To find the net torque acting on the cylinder, we can use the rotational motion equation:
Torque (τ) = Moment of inertia (I) × Angular acceleration (α).
Given that the cylinder starts from rest and reaches 200 rpm (revolutions per minute) in half a minute, we can calculate the angular acceleration. First, we convert the angular velocity from rpm to radians per second (rad/s):
ω = (200 rpm) × (2π rad/1 min) × (1 min/60 s) = 20π rad/s.
The angular acceleration (α) can be calculated by dividing the change in angular velocity (Δω) by the time taken (Δt):
α = Δω/Δt = (20π rad/s - 0 rad/s)/(30 s - 0 s) = (20π/30) rad/s².
Next, we need to calculate the moment of inertia (I) for the cylinder. The moment of inertia of a solid cylinder rotating about its central axis is given by:
I = (1/2)mr²,
where m is the mass of the cylinder and r is its radius.
Converting the mass of the cylinder from grams to kilograms, we have:
m = 20 g = 0.02 kg.
Substituting the values of m and r into the moment of inertia equation, we get:
I = (1/2)(0.02 kg)(0.05 m)² = 2.5 × 10⁻⁵ kg·m².
Now, we can calculate the net torque by multiplying the moment of inertia (I) by the angular acceleration (α):
τ = I × α = (2.5 × 10⁻⁵ kg·m²) × (20π/30) rad/s² ≈ 0.031 N·m.
Therefore, the net torque acting on the cylinder is approximately 0.031 N·m.
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A golf ball with mass 5.0 x 10^-2 kg is struck with a club
and leaves the club face with a velocity of +44m/s. find the
magnitude of the impulse due to Collison
The magnitude of the impulse due to the collision is 2.2 kg·m/s.
The impulse due to the collision can be calculated using the principle of conservation of momentum.
Impulse = change in momentum
Since the golf ball leaves the club face with a velocity of +44 m/s, the change in momentum can be calculated as:
Change in momentum = (final momentum) - (initial momentum)
The initial momentum is given by the product of the mass and initial velocity, and the final momentum is given by the product of the mass and final velocity.
Initial momentum = (mass) * (initial velocity) = (5.0 x 10^-2 kg) * (0 m/s) = 0 kg·m/s
Final momentum = (mass) * (final velocity) = (5.0 x 10^-2 kg) * (+44 m/s) = +2.2 kg·m/s
Therefore, the change in momentum is:
Change in momentum = +2.2 kg·m/s - 0 kg·m/s = +2.2 kg·m/s
The magnitude of the impulse due to the collision is equal to the magnitude of the change in momentum, which is:
|Impulse| = |Change in momentum| = |+2.2 kg·m/s| = 2.2 kg·m/s
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How do the vibrational and rotational levels of heavy hydrogen (D²) molecules compare with those of H² molecules?
The vibrational and rotational levels of heavy hydrogen (D²) molecules are similar to those of H² molecules, but with some differences due to the difference in mass between hydrogen (H) and deuterium (D).
The vibrational and rotational levels of diatomic molecules are governed by the principles of quantum mechanics. In the case of H² and D² molecules, the key difference lies in the mass of the hydrogen isotopes.
The vibrational energy levels of a molecule are determined by the reduced mass, which takes into account the masses of both atoms. The reduced mass (μ) is given by the formula:
μ = (m₁ * m₂) / (m₁ + m₂)
For H² molecules, since both atoms are hydrogen (H), the reduced mass is equal to the mass of a single hydrogen atom (m_H).
For D² molecules, the reduced mass will be different since deuterium (D) has twice the mass of hydrogen (H).
Therefore, the vibrational energy levels of D² molecules will be shifted to higher energies compared to H² molecules. This is because the heavier mass of deuterium leads to a higher reduced mass, resulting in higher vibrational energy levels.
On the other hand, the rotational energy levels of diatomic molecules depend only on the moment of inertia (I) of the molecule. The moment of inertia is given by:
I = μ * R²
Since the reduced mass (μ) changes for D² molecules, the moment of inertia will also change. This will lead to different rotational energy levels compared to H² molecules.
The vibrational and rotational energy levels of heavy hydrogen (D²) molecules, compared to H² molecules, are affected by the difference in mass between hydrogen (H) and deuterium (D). The vibrational energy levels of D² molecules are shifted to higher energies due to the increased mass, resulting in higher vibrational states.
Similarly, the rotational energy levels of D² molecules will differ from those of H² molecules due to the change in moment of inertia resulting from the different reduced mass. These differences in energy levels arise from the fundamental principles of quantum mechanics and have implications for the spectroscopy and behavior of heavy hydrogen molecules compared to regular hydrogen molecules.
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Explain how stellar evolution, and the universe would be
different if carbon was the most bound element instead of Iron.
If carbon were the most bound element instead of iron, stellar evolution and the universe would be significantly different. Carbon-based life forms would be more common, and the formation of heavy elements through stellar nucleosynthesis would be altered.
If carbon were the most bound element instead of iron, several implications would arise:
Stellar Evolution: Carbon fusion would become the primary process in stellar nucleosynthesis, leading to a different sequence of stellar evolution. Stars would undergo carbon burning, producing heavier elements and releasing energy.
The life cycle of stars, their sizes, lifetimes, and eventual fates would be modified.
Abundance of Carbon:
Carbon-based molecules, essential for life as we know it, would be more prevalent throughout the universe.
Carbon-rich environments would be more common, potentially supporting a wider range of organic chemistry and the development of carbon-based life forms.
Element Formation: The synthesis of heavier elements through stellar nucleosynthesis would be affected.
Iron is a crucial element for the formation of heavy elements through processes like supernova explosions. If carbon were the most bound element, alternative mechanisms for heavy element formation would emerge, potentially leading to a different abundance and distribution of elements in the universe.
Overall, the universe's composition, the prevalence of carbon-based life, and the processes involved in stellar evolution and element formation would be significantly different if carbon were the most bound element instead of iron.
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In a microwave receiver circuit, the resistance R of a wire 1 m long is given by R= k/d^2
z Where d is the diameter of the wire. Find R if k=0.00000002019 omega m^2 and d = 0.00007892 m.
The resistance (R) of the wire is approximately 32.138 ohms, calculated using the given values and the equation R = k / (d^2z).
To find the resistance R of the wire, we can substitute the given values into the equation R = k/d^2z.
k = 0.00000002019 Ωm^2
d = 0.00007892 m
z = 1 (since it is not specified)
Substituting these values:
R = k / (d^2z)
R = 0.00000002019 Ωm^2 / (0.00007892 m)^2 * 1
Calculating the result:
R ≈ 32.138 Ω
Therefore, the resistance R of the wire is approximately 32.138 ohms.
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In an engine, a piston oscillates with simple harmonic motion so that its position varies according to the expression x = 9.8 cos (14.5 t + 1.6) where x is in centimeters and t is in seconds. What is the Amplitude? What is the Angular Frequency? What is the Period?Find the initial position of the piston (t = 0). Find the initial velocity of the piston (t = 0). Find the initial acceleration of the piston (t = 0).
The amplitude of the piston's oscillation is 9.8 centimeters. The angular frequency is 14.5 radians per second. The period of the motion is approximately 0.436 seconds.
The given expression for the position of the piston, x = 9.8 cos (14.5 t + 1.6), represents simple harmonic motion. In this expression, the coefficient of the cosine function, 9.8, represents the amplitude of the oscillation. Therefore, the amplitude of the piston's motion is 9.8 centimeters.
The angular frequency of the oscillation can be determined by comparing the argument of the cosine function, 14.5 t + 1.6, with the general form of simple harmonic motion, ωt + φ, where ω is the angular frequency. In this case, the angular frequency is 14.5 radians per second. The angular frequency determines how quickly the oscillation repeats itself.
The period of the motion can be calculated using the formula T = 2π/ω, where T represents the period and ω is the angular frequency. Plugging in the value of ω = 14.5, we find that the period is approximately 0.436 seconds. The period represents the time taken for one complete cycle of the oscillation.
To find the initial position of the piston at t = 0, we substitute t = 0 into the given expression for x. Doing so gives us x = 9.8 cos (1.6). Evaluating this expression, we can find the specific value of the initial position.
The initial velocity of the piston at t = 0 can be found by taking the derivative of the position function with respect to time, dx/dt. By differentiating x = 9.8 cos (14.5 t + 1.6) with respect to t, we can determine the initial velocity.
Similarly, the initial acceleration of the piston at t = 0 can be found by taking the second derivative of the position function with respect to time, d²x/dt². Differentiating the position function twice will yield the initial acceleration of the piston.
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What is the concentration of po43- in a 4.71 m solution of phosphoric acid (h3po4) at equilibrium?
The concentration of PO43- in a 4.71 M solution of phosphoric acid (H3PO4) at equilibrium cannot be determined without additional information about the acid dissociation constants. Since the solution is 4.71 M, the concentration of H3PO4 at equilibrium is also 4.71 M.
The concentration of PO43- in a 4.71 M solution of phosphoric acid (H3PO4) at equilibrium can be determined by considering the dissociation of phosphoric acid in water. Phosphoric acid, H3PO4, is a weak acid that partially dissociates in water.
The balanced equation for the dissociation of H3PO4 is as follows:
H3PO4 ⇌ H+ + H2PO4-
H2PO4- ⇌ H+ + HPO42-
HPO42- ⇌ H+ + PO43-
At equilibrium, a certain amount of H3PO4 will dissociate into H+, H2PO4-, HPO42-, and PO43-. Since we are interested in the concentration of PO43-, we need to determine the concentration of H3PO4 at equilibrium.
Since the solution is 4.71 M, the concentration of H3PO4 at equilibrium is also 4.71 M.
The extent of dissociation depends on the acid dissociation constant, Ka, for each step of the dissociation. Without knowing the values of Ka, we cannot determine the exact concentration of PO43-. We would need more information to calculate the concentration of PO43- accurately.
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Explain within 150 words why cool lakes can form natural sound
amplifiers on a clear shiny morning?
On a clear and shiny morning, cool lakes can form natural sound amplifiers. This phenomenon is because of the temperature difference between the water and the air above it. The surface of the lake warms more slowly than the air, so the air near the water is cooler and denser than the air above it.
When sound waves travel through this denser layer of air, they refract or bend downward towards the surface of the lake. As the sound waves move towards the surface of the lake, they are met with an increasingly cooler and denser layer of air. This creates a sound channel, similar to a fiber optic cable, that carries the sound waves across the lake.
The sound channel extends to the middle of the lake where it reaches the opposite shore, where it can be heard clearly. The shape of the lake can also affect the amplification of sound. If a lake is bowl-shaped, sound waves will be reflected back towards the center of the lake, resulting in even greater amplification. This amplification can result in the sound traveling further and clearer than it would in normal conditions. This is why cool lakes can form natural sound amplifiers on a clear shiny morning, making it easier to hear sounds that would usually be difficult to pick up.
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Imagine you had a device to use for this experiment. The device would shoot a series of 2. 0 g balls along the surface at the box, each with a velocity of 30 cm/s [E60N]. In 2. 0 s it shoots 10 successive 2. 0 balls, all of which collide and rebound off the 100g box, as with the first ball. What would be the total impulse delivered to the box by the 10 collisions?What would be the total change in momentum of the 100g box?What would be the total change in velocity of the 100g box after these 10 collisions?
The total impulse delivered to the box by the 10 collisions is 0.006 kg·m/s, the total change in momentum of the 100 g box is 0.012 kg·m/s, and the total change in velocity of the 100 g box after these 10 collisions is 0.12 m/s.
The total impulse delivered to the box by the 10 collisions can be calculated using the equation:
Impulse = Change in Momentum
First, let's calculate the momentum of each 2.0 g ball. The momentum of an object is given by the equation:
Momentum = mass x velocity
Since the mass of each ball is 2.0 g and the velocity is 30 cm/s, we convert the mass to kg and the velocity to m/s:
mass = 2.0 g = 0.002 kg
velocity = 30 cm/s = 0.3 m/s
Now, we can calculate the momentum of each ball:
Momentum = 0.002 kg x 0.3 m/s = 0.0006 kg·m/s
Since 10 balls are shot in succession, the total impulse delivered to the box is the sum of the impulses from each ball. Therefore, we multiply the momentum of each ball by the number of balls (10) to find the total impulse:
Total Impulse = 0.0006 kg·m/s x 10 = 0.006 kg·m/s
Next, let's calculate the total change in momentum of the 100 g box. The initial momentum of the box is zero since it is at rest. After each collision, the box gains momentum in the opposite direction to the ball's momentum. Since the box rebounds off the ball with the same momentum, the change in momentum for each collision is twice the momentum of the ball. Therefore, the total change in momentum of the box is:
Total Change in Momentum = 2 x Total Impulse = 2 x 0.006 kg·m/s = 0.012 kg·m/s
Finally, let's calculate the total change in velocity of the 100 g box after these 10 collisions. The change in velocity can be found using the equation:
Change in Velocity = Change in Momentum / Mass
The mass of the box is 100 g = 0.1 kg. Therefore, the total change in velocity is:
Total Change in Velocity = Total Change in Momentum / Mass = 0.012 kg·m/s / 0.1 kg = 0.12 m/s
Therefore, the total impulse delivered to the box by the 10 collisions is 0.006 kg·m/s, the total change in momentum of the 100 g box is 0.012 kg·m/s, and the total change in velocity of the 100 g box after these 10 collisions is 0.12 m/s.
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An object of mass 0.2 kg is hung from a spring whose spring constant is 80 N/m. The object is subject to a resistive force given by - bå, where is its velocity in meters per second and b = 4 Nm-sec. (a) Set up differnetial equation of motion for free oscillations of the system and find the period of such oscillations. (b)The object is subjected to a sinusoidal driving force given by F(t) = Fosin(wt), where Fo = 2 N and w = 30 sec-1. In the steady state, what is the amplitude of the forced oscillation? (c) Find Q for the system - is the system underdamped, overdamped or critically damped? (d) What is the mean power input? (e) What is the energy
The differential equation of motion for free oscillations of the system can be derived using Newton's second law. The period of such oscillations is about 1.256 s. The amplitude of the forced oscillation is 0.056 N. The total energy of the system is the sum of the potential energy and the kinetic energy at any given time.
(a) The differential equation of motion for free oscillations of the system can be derived using Newton's second law:
m * d^2x/dt^2 + b * dx/dt + k * x = 0
Where:
m = mass of the object (0.2 kg)
b = damping coefficient (4 N·s/m)
k = spring constant (80 N/m)
x = displacement of the object from the equilibrium position
To find the period of such oscillations, we can rearrange the equation as follows:
m * d^2x/dt^2 + b * dx/dt + k * x = 0
d^2x/dt^2 + (b/m) * dx/dt + (k/m) * x = 0
Comparing this equation with the standard form of a second-order linear homogeneous differential equation, we can see that:
ω0^2 = k/m
2ζω0 = b/m
where ω0 is the natural frequency and ζ is the damping ratio.
The period of the oscillations can be found using the formula:
T = 2π/ω0 = 2π * sqrt(m/k)
Substituting the given values, we have:
T = 2π * sqrt(0.2/80) ≈ 1.256 s
(b) The amplitude of the forced oscillation in the steady state can be found by calculating the steady-state response of the system to the sinusoidal driving force.
The amplitude A of the forced oscillation is given by:
A = Fo / sqrt((k - m * w^2)^2 + (b * w)^2)
Substituting the given values, we have:
A = 2 / sqrt((80 - 0.2 * (30)^2)^2 + (4 * 30)^2) ≈ 0.056 N
(c) The quality factor Q for the system can be calculated using the formula:
Q = ω0 / (2ζ)
where ω0 is the natural frequency and ζ is the damping ratio.
Given that ω0 = sqrt(k/m) and ζ = b / (2m), we can substitute the given values and calculate Q.
(d) The mean power input can be calculated as the average of the product of force and velocity over one complete cycle of oscillation.
Mean power input = (1/T) * ∫[0 to T] F(t) * v(t) dt
where F(t) = Fo * sin(wt) and v(t) is the velocity of the object.
(e) The energy of the system can be calculated as the sum of the potential energy and the kinetic energy.
Potential energy = (1/2) * k * x^2
Kinetic energy = (1/2) * m * v^2
The total energy of the system is the sum of the potential energy and the kinetic energy at any given time.
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A 67-g ice cube at 0°C is heated until 60.3 g has become water at 100°C and 6.7 g has become steam at 100°C. How much energy was added to accomplish the transformation?
Approximately 150,645 Joules of energy need to be added to accomplish the transformation of the ice cube into steam.
To determine the amount of energy added to accomplish the transformation of the ice cube, we need to consider the different phases and the energy required for each phase change.
First, we calculate the energy required to heat the ice cube from 0°C to its melting point, which is 0°C. We can use the equation Q = mcΔT, where Q is the energy, m is the mass, c is the specific heat capacity, and ΔT is the temperature change. The specific heat capacity of ice is approximately 2.09 J/g°C.
Next, we calculate the energy required to melt the ice cube at its melting point. This is given by the equation Q = mL, where Q is the energy, m is the mass, and L is the latent heat of fusion. The latent heat of fusion for water is approximately 334 J/g.
Then, we calculate the energy required to heat the water from 0°C to 100°C using the equation Q = mcΔT, where c is the specific heat capacity of water (approximately 4.18 J/g°C).
Finally, we calculate the energy required to convert the remaining mass of water into steam at 100°C using the equation Q = mL, where L is the latent heat of vaporization. The latent heat of vaporization for water is approximately 2260 J/g.
By summing up these energy values, we can determine the total energy added to accomplish the transformation.
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An electron is shot vertically upward through the tiny holes in the center of a parallel-plate capacitor. If the initial speed of the electron at the hole in the bottom plate of the capacitor is 4.00
Given Data: The initial speed of the electron at the hole in the bottom plate of the capacitor is 4.00.What is the final kinetic energy of the electron when it reaches the top plate of the capacitor? Explanation: The potential energy of the electron is given by, PE = q V Where q is the charge of the electron.
V is the potential difference across the capacitor. As the potential difference across the capacitor is constant, the potential energy of the electron will be converted to kinetic energy as the electron moves from the bottom to the top of the capacitor. Thus, the final kinetic energy of the electron is equal to the initial potential energy of the electron. K.E = P.E = qV Thus, K.E = eV Where e is the charge of the electron. K.E = 1.60 × 10-19 × 1000 × 5K.E = 8 × 10-16 Joule, the final kinetic energy of the electron when it reaches the top plate of the capacitor is 8 × 10-16 Joule.
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1. Using Kirchhoff's rule, find the current in amperes on each resistor. www www. R₁ 252 R₂ 32 25V 10V R3 10 +
Kirchhoff's rules are fundamental in the study of electric circuits. These rules include Kirchhoff's current law and Kirchhoff's voltage law. Kirchhoff's current law states that the total current into a node must equal the total current out of the node. Kirchhoff's voltage law states that the total voltage around any closed loop in a circuit must equal zero. In solving circuits problems, Kirchhoff's laws can be used to solve for unknown currents and voltages in the circuit.
The circuit in question can be analyzed using Kirchhoff's laws. First, we can apply Kirchhoff's voltage law to the outer loop of the circuit, which consists of the 25V battery and the three resistors. Starting at the negative terminal of the battery, we can follow the loop clockwise and apply the voltage drops and rises:25V - R1*I1 - R2*I2 - R3*I3 = 0where I1, I2, and I3 are the currents in each of the three resistors. This equation represents the conservation of energy in the circuit.Next, we can apply Kirchhoff's current law to each node in the circuit.
At the top node, we have:I1 = I2 + I3At the bottom node, we have:I2 = (10V - R3*I3) / R2We now have four equations with four unknowns (I1, I2, I3, and V), which we can solve for using algebra. Substituting the second equation into the first equation and simplifying yields:I1 = (10V - R3*I3) / R2 + I3We can then substitute this expression for I1 into the equation from Kirchhoff's voltage law and solve for I3:(25V - R1*((10V - R3*I3) / R2 + I3) - R2*I2 - R3*I3) / R3 = I3Solving for I3 using this equation requires either numerical methods or some trial and error. However, once we find I3, we can use the second equation above to find I2, and then the first equation to find I1.
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Two resistors have resistances R(smaller) and R(larger), where R(smaller) < R(larger). When the resistors are connected in series to a 12.0-V battery, the current from the battery is 1.51 A. When the resistors are connected in parallel to the battery, the total current from
the battery is 9.45 A Determine the two resistances.
The values of the two resistances are 1.56 ohm's and 6.45 ohms
What is ohm's law?Ohm's Law is a formula used to calculate the relationship between voltage, current and resistance in an electrical circuit.
Ohm's law states that the current passing through a metallic conductor is directly proportional to the potential difference between the ends of the conductor, provided, temperature and other physical condition are kept constant.
V = 1R
represent the small resistor by a and the larger resistor by b
When they are connected parallel , total resistance = 1/a + 1/b = (b+a)/ab = ab/(b+a)
When they are connected in series = a+b
a+b = 12/1.51
ab/(b+a) = 12/9.45
therefore;
a+b = 7.95
ab/(a+b) = 1.27
ab = 1.27( a+b)
ab = 1.27 × 7.95
ab = 10.1
Therefore the product of the resistances is 10.1 and the sum of the resistances is 7.95
Therefore the two resistances are 1.56ohms and 6.45 ohms
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The two resistances are R(smaller) = 2.25 Ω and R(larger) = 5.70 Ω.
The resistances of two resistors are R (smaller) and R (larger).R (smaller) < R (larger).Resistors are connected in series with a 12.0 V battery. The current from the battery is 1.51 A. Resistors are connected in parallel with the battery.The total current from the battery is 9.45 A.
The two resistances of the resistors.
Lets start by calculating the equivalent resistance in series. The equivalent resistance in series is equal to the sum of the resistance of the two resistors. R(total) = R(smaller) + R(larger) ..... (i)
According to Ohm's Law, V = IR(total)12 = 1.51 × R(total)R(total) = 12 / 1.51= 7.95 Ω..... (ii)
Now let's find the equivalent resistance in parallel. The equivalent resistance in parallel is given by the formula R(total) = (R(smaller) R(larger)) / (R(smaller) + R(larger)) ..... (iii)
Using Ohm's law, the total current from the battery is given byI = V/R(total)9.45 = 12 / R(total)R(total) = 12 / 9.45= 1.267 Ω..... (iv)
By equating equation (ii) and (iv), we get, R(smaller) + R(larger) = 7.95 ..... (v)(R(smaller) R(larger)) / (R(smaller) + R(larger)) = 1.267 ..... (vi)
Simplifying equation (vi), we getR(larger) = 2.533 R(smaller) ..... (vii)
Substituting equation (vii) in equation (v), we get R(smaller) + 2.533 R(smaller) = 7.953.533 R(smaller) = 7.95R(smaller) = 7.95 / 3.533= 2.25 ΩPutting the value of R(smaller) in equation (vii), we getR(larger) = 2.533 × 2.25= 5.70 Ω
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A stone with a mass of 4.00 kg is moving with velocity (7.001 - 2.00)) m/s. (HINT: ² =) (a) What is the stone's kinetic energy (in 3) at this velocity? (b) Find the net work (in 3) on the stone if its velocity changes to (8.001 + 4.00j) m/s.
The problem involves calculating the kinetic energy of a stone moving with a given velocity and finding the net work done on the stone when its velocity changes to a different value.
(a) The kinetic energy of an object can be calculated using the equation KE = (1/2)mv², where KE is the kinetic energy, m is the mass of the object, and v is its velocity. Given that the mass of the stone is 4.00 kg and its velocity is (7.001 - 2.00) m/s, we can calculate the kinetic energy as follows:
KE = (1/2)(4.00 kg)((7.001 - 2.00) m/s)² = (1/2)(4.00 kg)(5.001 m/s)² = 50.01 J
Therefore, the stone's kinetic energy at this velocity is 50.01 J.
(b) To find the net work done on the stone when its velocity changes to (8.001 + 4.00j) m/s, we need to consider the change in kinetic energy. The net work done is equal to the change in kinetic energy. Given that the stone's initial kinetic energy is 50.01 J, we can calculate the change in kinetic energy as follows:
Change in KE = Final KE - Initial KE = (1/2)(4.00 kg)((8.001 + 4.00j) m/s)² - 50.01 J
The exact value of the net work done will depend on the specific values of the final velocity components (8.001 and 4.00j).
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