Answer:
The correct option is;
C. 25 m/s
Explanation:
The initial velocity with which the boulder was thrown = 25 m/s
The path in which the boulder projectile moves = 30°
For projectile motion, we have;
The time it takes the boulder to hit the ground is given by the following equation;
y = y₀ + v₀·sin(θ₀)t -¹/₂·g·t²
Where;
y = The height of the boulder
y₀ = The initial height of the boulder = 0
g = The acceleration due to gravity = 9.81 m/s²
When the boulder touches the ground again, the value of y = 0. therefore, we have;
0 = 0 + 25 × sin(30)t -¹/₂ × 9.81 × t²= 12.5·t - 4.905·t²
From which we have, t = 0 or t ≈ 2.55 s
At t = 2.55 s The vertical velocity = v₀sin(θ₀) - g·t = 25 × 0.5 - 9.81×2.55 = -12.5 m/s
The vertical velocity, [tex]v_y[/tex] = -12.5 m/s
The horizontal velocity, vₓ = v₀·cos(θ₀) = 25×cos(30) ≈ 21.65 m/s
The magnitude of the resultant velocity before, the boulder hits the ground is given as follows
[tex]\left | v \right |[/tex] = √((vₓ)² + ([tex]v_y[/tex])²) = √(12.5² + 21.65²) = √625 = 25
The magnitude of the resultant velocity before, the boulder hits the ground is 25 m/c
A 2000 kg car moves along a horizontal road at speed vo
15.9 m/s. The road is
wet, so the static friction coefficient between
the tires and the road is only pls 0.105 and
the kinetic friction coefficient is even lower,
= 0.0735.
The acceleration of gravity is 9.8 m/s2.
What is the shortest possible stopping dis-
tance for the car under such conditions? Use
g= 9.8 m/s² and neglect the reaction time of
the driver.
Answer in units of m.
Answer:
The shortest possible stopping distance of the car is 175.319 meters.
Explanation:
In this case we see that driver use the brakes to stop the car by means of kinetic friction force. Deceleration of the car is directly proportional to kinetic friction coefficient and can be determined by Second Newton's Law:
[tex]\Sigma F_{x} = -\mu_{k}\cdot N = m \cdot a[/tex] (Eq. 1)
[tex]\Sigma F_{y} = N-m\cdot g = 0[/tex] (Eq. 2)
After quick handling, we get that deceleration experimented by the car is equal to:
[tex]a = -\mu_{k}\cdot g[/tex] (Eq. 3)
Where:
[tex]a[/tex] - Deceleration of the car, measured in meters per square second.
[tex]\mu_{k}[/tex] - Kinetic coefficient of friction, dimensionless.
[tex]g[/tex] - Gravitational acceleration, measured in meters per square second.
If we know that [tex]\mu_{k} = 0.0735[/tex] and [tex]g = 9.807\,\frac{m}{s^{2}}[/tex], then deceleration of the car is:
[tex]a = -(0.0735)\cdot (9.807\,\frac{m}{s^{2}} )[/tex]
[tex]a = -0.721\,\frac{m}{s^{2}}[/tex]
The stopping distance of the car ([tex]\Delta s[/tex]), measured in meters, is determined from the following kinematic expression:
[tex]\Delta s = \frac{v^{2}-v_{o}^{2}}{2\cdot a}[/tex] (Eq. 4)
Where:
[tex]v_{o}[/tex] - Initial speed of the car, measured in meters per second.
[tex]v[/tex] - Final speed of the car, measured in meters per second.
If we know that [tex]v_{o} = 15.9\,\frac{m}{s}[/tex], [tex]v = 0\,\frac{m}{s}[/tex] and [tex]a = -0.721\,\frac{m}{s^{2}}[/tex], stopping distance of the car is:
[tex]\Delta s = \frac{\left(0\,\frac{m}{s} \right)^{2}-\left(15.9\,\frac{m}{s} \right)^{2}}{2\cdot \left(-0.721\,\frac{m}{s^{2}} \right)}[/tex]
[tex]\Delta s = 175.319\,m[/tex]
The shortest possible stopping distance of the car is 175.319 meters.
What is a scientific theory?
Answer:
Scientific theories are explanations of some aspect of the natural world based on repeated observations.
Hope this helps!!!!
Answer:
The way that scientists use the word 'theory' is a little different than how it is commonly used in the lay public," said Jaime Tanner, a professor of biology at Marlboro College. "Most people use the word 'theory' to mean an idea or hunch that someone has, but in science the word 'theory' refers to the way that we interpret facts.
Explanation:
A 68 kg runner exerts a force of 59 N. What is the acceleration of the
runner?
0 m/s2
1.16 m/s2
4012 m/s2
0.87 m/s2
d) ≈ 0.87 m/s²
Explanation:Hi there !
Newton's second lawF = m×a => a = F/m
a = 59N/68kg
1 N = 1kg·m/s²
= (59kg·m/s²)/68kg
= 0.8676 m/s²
≈ 0.87 m/s²
Good luck !
A tree is turned into sawdust is that physical change or chemical change?
Answer:
Physical change
Explanation:
A physical change can be reversible where the original form of the matter can be restored, or irreversible where the original form cannot be restored. Therefore, sawdust is a physical change.
A ball of mass 200 g rolls along the ground at a speed of 5.2 m/s. Calculate the kinetic energy of the ball.
Answer:
We have a mass of 200g (0.2kg) moving at 20m/s
Kinetic Energy KE = ½ mv^2 where m is mass and v is velocity
Actually, v is a vector quantity, so KE = ½ mv•v
The dot product of 2 vectors a and b is abCosθ where θ is the angle between the vectors.
Obviously v•v = v^2 Cos0 = v^2
In this case, we have KE = ½ (0.2)(20^2) = 40kg-m^2/s^2 = 40J
So we have kinetic energy in the amount of 40 Joules.
Explanation:
The right answer is "2.7 J"
Answer explanation:
Remember to convert grams to kilograms first by dividing by 1000.
Kinetic energy
= 1/2 × mass × speed2
= 1/2 × 0.2 kg × (5.2 m/s)^2
= 2.7 J (to 2 sig. fig.)
Hope it helps ✨✨
A battery of emf 24v and terminal resistance 4 ohms is connected to a resistor of 32 ohms. What is the terminal pd of the battery?
Answer:
21.3V
Explanation:
Explanation
E = V + Ir
V = E- Ir
V = 24 - {(24/36) x 4}
V = 21.3V
What is better for measuring how hard you are actually working, Target Heart Rate or Rating of perceived exertion?
Answer:
Rating of percieved exertion
PLEASE HURRYYYYYY:
Students had two batteries and two different resistors. During four trials, they build four different circuits and plan to measure the circuit’s current in Amps according to the following table.
Trial Number
Voltage (V)
Resistance (Ω)
Current (A)
1
1.5
200
2
1.5
100
3
3.0
200
4
3.0
100
For which trial would the students measure the smallest current in the circuit?
Answer: C. Trial 3
Explanation:
Trial 1 and 2 equal 1.5, Trial 3 equals 1 and Trial 4 equals 3. Trial 3 is the smallest current .
The trial for which the students would measure the smallest current is the circuit is trial 2 and trial 3.
To know the trial which generates the smallest current, we need to determine the current in each trial.
Since current I = V/R where V = voltage and R = resistance.
For trial 1, V = 1.5 V and R = 200 Ω
So, I = 1.5 V/200 Ω
= 0.0075 A
= 7.5 mA
For trial 2, V = 1.5 V and R = 100 Ω
So, I = 1.5 V/100 Ω
= 0.015 A
= 15 mA
For trial 3, V = 3 V and R = 200 Ω
So, I = 3 V/200 Ω
= 0.015 A
= 15 mA
For trial 4, V = 3 V and R = 100 Ω
So, I = 3 V/100 Ω
= 0.03 A
= 3 mA
Trial 2 and trial 3 both produce a the smallest current of 15 mA.
So, the trial for which the students would measure the smallest current is the circuit is trial 2 and trial 3.
Learn more about current here:
https://brainly.com/question/996480
If a hypothesis is.......
additional tests should be done to ensure accurate results.
a. correct
b.incorrect
c. unknown
d. inconclusive
Answer:
a correct
Explanation:
a hypothesis is a supposition made of a basis of limited evidence
Fy is the reaction force from Plate Y. What Statement best describes the action and reaction forces on the plates? Tectonic plates
Answer:
According to Newton's third law of motion, the reaction force is equal to the action force.
Explanation:
Newton's third law of motion states that for every action there is an equal and opposite reaction. This means that if one object exerts a force on a second object, the second object exerts an equal force in the opposite direction. When Plate X pushes on Plate Y with the action force (Fx), Plate Y must push back with an equal force (Fy).
Therefore, the best explanation is that according to Newton's third law of motion, the reaction force is equal to the action force.
For every action, there has equal and opposite reaction - this statement best describes the action and reaction forces on the plates.
What is Newton's 3rd law of motion?As a result of this interaction, there are two forces: one from plate X and one from plate Y. The third law of motion of Newton deals with these two forces, which are referred to as action and reaction forces. Newton's third law is officially expressed as follows: There is an equal and opposite reaction to every action.
The implication of the statement is that there are always two forces acting on the two interacting objects. The force acting on the first object is equal in size to the force acting on the second. The force acting on the first object is acting in the opposite direction to the force acting on the second object. Force pairs—equal and opposing action-reaction force pairs—always exist in pairs.
Learn more about force here:
https://brainly.com/question/13191643
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does anyone know how to do this
The mining-resource cycle determines the use of ore materials. Which step is not part of the cycle?
A)
exploring and extracting ores
B)
refining ores and creating products from ore materials
C)
marketing and selling products that use ore materials
D)
recycling and disposing of wastes from the steps and the products
Answer:
c) marketing and selling products that use ore materials
Someone, please help me with this
1. Distance traveled during the first minute (A-B) *
40 m
100 m
140 m
180 m
2. Displacement after the first minute (A-B) *
180 m west
180 m east
100 m west
100 m east
3. Distance traveled during the first 2 minutes (A-B-C)
40 m
140 m
320 m
420 m
4. Displacement after the first 2 minutes of travel (A-B-C) *
40 m east
40 m west
140 m east
140 m west
5. Distance traveled during the total time of 3 minutes (A-B-C-D) *
140 m
240 m
360 m
420 m
6. Displacement after the total 3 minutes of travel (A-B-C-D) *
40 m east
40 m west
140 m east
140 m west
Answer:
Explanation:
1). Distance traveled during the first minute (A-B)
= Distance from A to C + Distance from C to D + Distance from D to B
= 40 + 100 + 40
= 180 m
Option (4) will be the answer.
2). Displacement after first minute (A-B)
= Distance from A to B
= 180 m East
Option (2) is the answer.
3). Distance traveled during the first 2 minutes (A - B - C)
= Distance from A to B + Distance from B to C
= 180 + 140
= 320 m
Option (3) will be the answer.
4). Displacement after first 2 minutes (A-B-C)
= Distance between A and C
= 40 m towards east
Option (1) is the answer.
5). Distance traveled during 3 minutes (A-B-C-D)
= Distance between A to B + Distance between B to C + Distance between C to D
= 180 + 140 + 100
= 420 m
Option (4) is the answer.
6). Displacement after total 3 minutes (A-B-C-D)
= Distance between A and D
= Distance between A to C + distance between C to D
= 40 + 100
= 140 m
And the direction is towards East.
Option (3) is the answer.
The frequency of a F-sharp sound wave in music is 370 Hz, and its wavelength is 0.93 m. what is the wave speed?
Answer:
wave speed =344.1 m/s
using v=fΠ
where v is the speed
The wave speed will be 344.1 m/sec. The wave speed is found as the product of the wavelength and the frequency of the wave.
What is wavelength?The distance between two successive troughs or crests is known as the wavelength. The peak of the wave is the highest point, while the trough is the lowest.
The wavelength is also defined as the distance between two locations in a wave that have the same oscillation phase.
The given data in the problem is;
v is the speed = ?
f is the frequency= 370 Hz
λ is the wavelength of the wave=0.96 m
The relationship between the wave's wavelength, frequency, and speed is given as;
wavelength = speed of wave / frequency
[tex]\rm \lambda = \frac{v}{f} \\\\ v = \lambda \times f \\\\ v = 0.93 \times 370 \ Hz \\\\ v= 344.1 \ m/sec[/tex]
Hence, the wave speed will be 344.1 m/sec.
To learn more about the wavelength, refer to the link;
brainly.com/question/7143261
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1.) A hover disc is moving across a wooden floor with a constant velocity and virtually no friction. The soccer
disc runs into a baseball, which applies a force of 5 N opposing the motion of the disc. What will happen to
the soccer discs velocity
Answer:
The soccer discs will be change.
Explanation:
Given that,
Opposing force = 5 N
We know that,
Drag force :
Drag force is directly proportional to the square of velocity.
[tex]F_{d}\propto v^2[/tex]
[tex]F_{d}=\dfrac{1}{2}C\rho Av^2[/tex]
Where, C = drag constant
[tex]\rho[/tex] = density
A = area
v= velocity
We need to find what happen to the soccer discs velocity
According to drag force,
If we applies a force of 5 N opposing the motion of the disc then the velocity of the soccer discs will be change.
Hence, The soccer discs will be change.
What affect does doubling the net force have on the acceleration of the object (when
the mass of the object stays the same)? Identify a set of two trials that support your answer to question 1
===========================================================
Explanation:
Consider a mass of 10 kg, so m = 10
Let's say we apply a net force of 20 newtons, so F = 20
The acceleration 'a' is...
F = ma
20 = 10a
20/10 = a
2 = a
a = 2
The acceleration is 2 m/s^2. Every second, the velocity increases by 10 m/s.
---------------
Now let's double the net force on the object
F = 20 goes to F = 40
m = 10 stays the same
F = ma
40 = 10a
10a = 40
a = 40/10
a = 4
The acceleration has also doubled since earlier it was a = 2, but now it's a = 4.
---------------
In summary, if you double the net force applied to the object, then the acceleration doubles as well.
Acceleration is directly proportional to the net force on an object, and inversely proportional to its mass.
So if an object's mass stays the same while the net force on it doubles, then its acceleration will also double.
We don't know anything about the "trials". This sounds like it might be a follow-up to a lab experiment that was performed when we weren't there.
We also don't know anything about "question 1".
I need help with this physics question
a car travels 200m in 30 s and 400m in the next 90s. Whats the average speed?
Answer:
300m per minute or 5m per second
how many apples are in 29 trees if each tree has 45 apples?
Answer:
1305 I think but not sure
A loaf of bread bakes in an oven. The bread is on a rack about one foot above the heat source. However, the top of the bread cooks just as fast as the bottom. How is heat being added to the bread?
Answer:
the bread is getting heated from top and bottom because the oven is heated all over and the particles from the oven makes the bread's particles heat up and the bread will be done
Explanation:
i have the same answer
Answer:
The air is heated by the heat source in the oven. The hot air rises, surrounds the bread, and heats the bread on all sides.
Explanation:
20. Give an example of sublimation.
Answer:Explanation:
A common example of sublimation is the dry ice, heavy CO2.
what is measurement ?
Answer: Measurement is the assignment of a number to a characteristic of an object or event, which can be compared with other objects or events. The scope and application of measurement are dependent on the context and discipline. In the natural sciences and engineering, measurements do not apply to nominal properties of objects or events, which is consistent with the guidelines of the International vocabulary of metrology published by the International Bureau of Weights and Measures. However, in other fields such as statistics as well as the social and behavioural sciences, measurements can have multiple levels, which would include nominal, ordinal, interval and ratio scales.
Explanation:
22. Explain in detail what happens to particles before, during, and after vaporization.
Answer:
Vaporization occurs when a substance changes from a liquid to a gas. The molecules in a liquid are in constant motion while staying relatively close together due to intermolecular forces. When an increase in temperature occurs, the molecules' kinetic energy also increases. If a liquid is heated the particles are given more energy and move faster and faster expanding the liquid. The most energetic particles at the surface escape from the surface of the liquid as a vapor as it gets warmer. Liquids evaporate faster as they heat up and more particles have enough energy to break away.
Mark Me Brainliest If u Found it helpful
How do you calculate the radius of a planets orbit with mass and time ?
Answer:
By observing the time between transits, we know the orbital period. Kepler's Third law can be used to determine the orbital radius of the planet if the mass of the orbiting star is known (R3=T2−Mstar/Msun, the radius is in AU and the period is in earth years).
Explanation:
hope this helps!
Can you pls answer the 2 questions
Answer:
1) False, since constant speed means constant velocity, but with constant direction as well. Velocity is speed with direction. When you move in a circle, there are boundaries which means that a constant moving speed will cause the object to veer(move in different directions) to maintain movement, If it doesn't veer, the object will deflect(rebound) off the surface due to friction, and impact force or depending on its physical bond of malleability or density.
2a) Create position vectors by drawing a ray from the center(origin) of the circle to each of your desired points, it's magnitude will be the radius(how convenient). Both of these vectors go from the center of the circle to the position on the circle. In general, the distance from the origin to a point is called the radius vector.
2b)
what is the medium of the sound waves the student hears
Answer:
A
Explanation:
the air is the medium man
Answer:
the desk
Explanation:
The level of toluene (a flammable hydrocarbon) in a storage tank may fluctuate between 10 and 400 cm from the top of the tank. since it is impossible to see inside the tank, an open-end manometer with water or mercury as the manometer fluid is to be used to determine the toluene level. one leg of the manometer is attached to the tank 500 cm from the top. a nitrogen blanket at atmospheric pressure is maintained over the tank contents. felder, richard m.; rousseau, ronald w.; bullard, lisa g.. elementary principles of chemical processes, 4th edition (page 81). wiley. kindle edition.
Complete Question
The complete question is shown on the first and second uploaded image
Answer:
When water is used the reading is [tex] R = 2281.6 \ cm [/tex]
When mercury is used the reading is [tex] R = 23.83 \ cm [/tex]
The best fluid to use is mercury because for water a slight change in toluene level will cause a large change in height .
Explanation:
From the question we are told that
The length of the leg of the manometer to the top of the tank is d = 500cm
The toluene level where in the tank where the height of the manometer fluid level in the open arm is equal to the height where the manometer is connected to the tank is h =150 cm
The manometer reading is R
Generally at the point where the height of the open arm is equal to the height of the of the point connected to the tank ,
The pressure at the height of the both arms of the manometer corresponding to the base of the tank are equal
i.e [tex]P_1 = P_2[/tex]
Here [tex]P_1[/tex] is the pressure of the manometer at the point corresponding to the base of the tank and this is mathematically represented as
[tex] P_{atm} + P_1 = P_{atm} + P_t[/tex]
Here [tex]P_t[/tex] is the pressure due to the toluene level in the tank and in the arm of the manometer connected to the tank and this is mathematically represented as
[tex]P_t = \rho_t * g * h_i[/tex]
Here
[tex]\rho_t [/tex] is the density of toluene with value [tex]\rho_t = 867 kg/m^3 [/tex]
[tex]h_i[/tex] is the height of the connected arm above the point equivalent to the base of the tank , this mathematically represented as
[tex]h_i = d - h + R[/tex]
and [tex] P_2 [/tex] is the the pressure at the open arm of the manometer at the point equivalent to the base of the base of the tank and this is mathematically represented as
[tex] P_2 = \rho_f * g * h_f [/tex]
Here
[tex]\rho_f[/tex] is the density of the fluid in use , if it is water the density is
[tex]\rho_w = 1000 \ kg /m^3 [/tex]
and if it is mercury the density is
[tex]\rho_m = 13600 \ kg /m^3 [/tex]
[tex]h_f[/tex] is the height of the fluid in the open arm of the manometer from the point equivalent to the base of the tank which is equivalent the manometer reading R
So when the fluid is water we have
[tex] P_{atm} + \rho_t* g *(d - h + R) = P_{atm} + \rho_f * g * h_f[/tex]
=> [tex] \rho_t* (d - h + R) = \rho_w * h_f[/tex]
=> [tex] 867 (500 - 150 + R) = 1000 * R [/tex]
=> [tex] R = 2281.6 \ cm [/tex]
So when the fluid is mercury we have
[tex] \rho_t* (d - h + R) = \rho_m * h_f[/tex]
=> [tex] 867 (500 - 150 + R) = 13600 * R [/tex]
=> [tex] R = 23.83 \ cm [/tex]
The difference in the mercury reading for mercury due to the fact that they have different densities as we have seen in this calculation
So the best fluid to use is mercury because for water a slight change in toluene level will cause a large change in height .
I WILL GIVE BRAINLIEST A battery contains two metals that have different tendencies to attract electrons. If one is lithium with an electron affinity of −3.05, and the other is zinc with an electron affinity of −0.76, describe how the electrons will flow. Then, describe how you could make this an even stronger battery. (4 points)
Answer:
electrons will flow from lower (lithium) to higher (zinc)
You can make a stronger battery by having a larger electron affinity difference.
Hope this helps \(-._.-)/
Covert 1 mile to feet. Then convert to inches. Then covert to centimeters. How many centimeters are in a mile?
Answer:
160,934.4 cm or in other words *160,934*
Explanation:
1 mile = 5280 ft.
5280 ft. = 63360 in.
63360 in. = 160934.4
Polymetrics can help a person maintain cardiorespitory fitness T or F
Answer:
True
Explanation:
The term 'plyometrics' is used interchangeably with the term 'jump training'. The technique can be used for training in sports that require explosive movements.