Answer:
The correct answer is power
A runner starts from rest and speeds up with constant acceleration. If she
has gone a distance of 30 m at the point when she reaches a speed of 8 m/s,
what is her acceleration?
A. 7.5 m/s2
B. 3.8 m/s2
C. 9.1 m/s2
D. 1.1 m/s2
Answer:
a = 1.07 m/s^2
Explanation:
The computation of the acceleration is shown below:
As we know that
[tex]v_f^{2} - v_i^{2} = 2 ad[/tex]
where,
v_i = 0 m/s = initial speed
v f = 8 m/s = final speed
d = 30m = distance
Now placing these values to the above equation
[tex]8^{2} - 0 = 2 \times a \times 30[/tex]
64 = 60a
a = 1.07 m/s^2
We simply applied the above formula so that we could able to determine the acceleration
Suppose that a driver applies a force of 140 N to the master cylinder, which has a diameter equal to 14 the diameter of the brake cylinder. What is the force applied by the brake cylinder on the brake shoe?
Answer:
force on brake shoes is 10 N
Explanation:
for the master cylinder;
force applied = 140 N
diameter = 14d
for brake cylinder;
force applied on the brake shoe by the brake cylinder f = ?
diameter = d
The pressure will be transmitted undiminished from the master cylinder to the brake cylinder according to pascals pressure law.
pressure = force/area
but cross sectional area is proportional to diameter of the cylinder
therefore
[tex]\frac{140}{14d } = \frac{f}{d }[/tex]
the diameters will cancel out, and we're left with
force on brake shoes = 10 N
The speed of an electromagnetic wave is a constant, 3.0 × 108 m/s. The wavelength of a wave is 0.6 meters. What is the frequency?
Answer:
The answer to this should be: 5.0 x 10⁸ Hz
Explanation:
The speed, s, of a wave, equals the product of its frequency, ν, times its wavelength, λ:
s = νλ.
As the question states, the speed of an electromagnetic wave is a constant, c, equal to 3.0 × 10⁸ m/s.
Substituting this constant in the equation for the speed of the wave, you get:
c = νλ.
From that equation, you can solve for the frequency to show the inverse realation of frequency and wavelength:
ν = c / λ
Now, you just have to substitute values and compute, leaving you with:
5.0 x 10⁸ Hz
How is it possible to blow a balloon?
Explanation:
To blow up a balloon, start by pinching the neck of the balloon with your index finger and thumb. Then, take a deep breath and put the opening of the balloon in between your lips. When you're ready, loosen your grip on the neck and blow into the balloon opening so the balloon starts to fill with air.May
DOUBLE POINTS!
A tuning fork of 500 Hz is struck in a room with a speed of sound of 340 m/s. What is the distance between a point of rarefaction and the next compression point, in the resulting sound?
[tex]\mathfrak{\huge{\pink{\underline{\underline{AnSwEr:-}}}}}[/tex]
Actually Welcome to the Concept of the Waves and it's motion.
So we here apply the formula as,
Velocity = frequency*wavelength
so here we get as,
340 = 500 * Lambda
Lambda = 340/500
so we get the distance as,
L = 0.68 m
Answer:
λ = 0.68 m
Explanation:
Distance between a point of rarefaction and the next compression point is actually the wavelength (λ)
So, we'll find wavelength here:
Given:
Frequency = f = 500 Hz
Speed = v = 340 m/s
Required:
Wavelength = λ = ?
Formula:
v = f λ
Solution:
λ = v/f
λ = 340/500
λ = 0.68 m
Indicar tipo de unión química que presentan los siguientes compuestos. Realizar a representación de Lewis, molecular o iónica, según corresponda: a-CH4 b-SrO c-HBr d-NH3 e-Cl2O f-Li2O g-CO2 h-MgCl2
Answer:
Explanation:
a. CH₄- Covalent bonding(ligação covalente)
b. SrO- ionic bonding (ligação iônica)
c. HBr- Polar Covalent bonding (ligação covalente polar)
d. NH₃ - covalent bonding(ligação covalente)
e. Cl₂O - Covalent bonding (ligação covalente)
f. Li₂O- ionic bonding (ligação iônica)
g. CO₂ - double covalent bonding (ligação covalente dupla)
h. MgCl₂- ionic bonding(ligação iônica)
Determine the amount of time for polonium-210 to decay to one fourth its original quantity. The half-life of polonium-210 is 138 days. Explain.
Answer:
276 days
Explanation:
1/4 th of the original means 2 half lives
1 half life = 138 days
So,
2 half lives = 276 days
How is mercury barometer constructed ?
Answer:
A mercury barometer is a device use to measure stomspheric pressure and is constructed as following:
A mercury barometer requires a tube which has one close end, and one open end.Tube is placed upside down in a beaker in such a way so that one end open in the beaker and the other remain outside of the beaker. The barometric liquid (mercury) is then filled in the tube by pouring mercury liquid in the beaker.The position of tube creates vacuum between the closed end of the tube and liquid surface and the Mercury has high density that is why used as the liquid to measure pressure.
N2 + O2 → 2NO N-N triple bond: 941 kJ/mol O-O double bond: 495 kJ/mol N-O bond: 201 kJ/mol
Answer:
[tex]\large \boxed{\text{761 kJ}}[/tex]
Explanation:
You calculate the energy required to break all the bonds in the reactants.
Then you subtract the energy needed to break all the bonds in the products.
N₂ + O₂ ⟶ 2NO
N≡N + O=O ⟶ 2O-N=O
Bonds: 2N≡N 1O=O 2N-O + 2N=O
D/kJ·mol⁻¹: 941 495 201 607
[tex]\begin{array}{rcl}\Delta H & = & \sum{D_{\text{reactants}}} - \sum{D_{\text{products}}}\\& = & 2 \times 941 +1 \times 495 - (2 \times 201 + 2\times 607)\\&=& 2377 - 1616\\&=&\textbf{761 kJ}\\\end{array}\\\text{The enthalpy of reaction is $\large \boxed{\textbf{761 kJ}}$}.[/tex]
Newton’s third law of motion says that for every action there is a(n) and opposite reaction.
Answer:
for every action thete is an equal and opposite reaction
Answer:
Newton’s third law of motion says that for every action there is a(n)
equal and opposite reaction.
Explanation:
just got it right edg 1928
Q2. Zara travelled in a train moving at an average speed of 120km/h and covered a distance of 40km towards East. Calculate the time taken by the train to cover this distance.
Answer: 20 minutes
Explanation:
Given the following :
Average speed of train = 120km/hr
Distance = 40km.
The time take by the train moving at an average speed of 120km/hr to cover a distance of 40km due is ;
Recall:
Speed = distance / time
Therefore,
Time taken = distance covered / speed
Time taken = 40km / 120km/hr
Time taken = 1/ 3 hr
Therefore, 1/3 rd of an hour equals
1/3 × 60 = 20 minutes.
Time taken) 20 minutes
Time taken by tain to cover distance is 20 minutes as:
Distance= 40 km
Speed= 120 km/h
Time= distance/speed
= 40/120
= 1/3 hour
= 20 min
or =0.33 hrs
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A hydrogen bond is a special form of a(n)
a. covalent bond.
b. dipole-dipole force.
C. ionic bond.
d. London dispersion force.
Answer:
B
Explanation:
PLEASE HELP, THANK YOU!.. :)
Answer:
First Reaction:
[tex]^{234}U[/tex] => [tex]^{230} Th + ^{4}He[/tex]
Second Reaction:
[tex]^{230} Th[/tex] => [tex]^{226} Ra + ^{4}He[/tex]
Combined Reaction:
[tex]^{234} U[/tex] => [tex]^{226}Ra + 2( ^{4} He)[/tex]
I NEED HELP PLEASE, THANKS! :)
Generate an explanation for the following formula: P = I²R . Explain.
Answer:
P = VI = (IR)I = I2R
Explanation:
What the equation means is that if you double the current you end up with 4 times the power loss. It's like the area of carpet you need for a room - if you make the room twice as long and twice as wide you need 4x as much carpet. The physical explanation is that the voltage difference along a wire depends on the current - more current flowing with a resistance means more voltage (pressure of electricity if you like) is built up.
This extra voltage means more power. So if you double the current your would double the power, but you also double the voltage which doubles the power again = 4x as much power. P = VI = (IR)I = I2R
I hope this helps you out, if I'm wrong, just tell me.
As I mentioned earlier, Ohm's law gives us the formula P = IV, where V is the voltage ( also known as the electrical potential difference ) and I is the current. It is confusing that P = I²R and P = IV are one in the same - so I want to go a bit deeper on that.
We have three formulas, P = IV, P = I²R, and P = V² / R. Each are considered the same. The two formulas P = I²R, and P = V² / R are derived from the statement that P = IV, under the condition V = IR. Substitute the value of V from this second condition V = IR into P = IV. You would get the following -
P = I( IR ),
P = I²R
That is how one can derive the formula P = I²R, and how P = IV and P = I²R are thought to be one in the same. If you would like, take a look at how to get the formula " P = V² / R, "
V = IR, P = IV
I = V / R, P = IV
P = ( V / R )V,
P = V² / R
Hope that helps!
A friend of yours who has not taken an astronomy class looks at your textbook and really likes the picture of the Pleiades, a cluster of stars surrounded by a bluish reflection nebula. She wants to know what causes that beautiful blue glow. To explain it to her, you want to compare the process that causes the blue glow to something that is in your friend's everyday experience. Which of the following terrestrial phenomena is the result of the same type of process that makes a reflection nebula in space?
A. the blueish glow of the flame on a gas stove
B. the blue light you see reflected from a blue sweater
C. the blue colour of the Earth's sky
D. the blue-white colour of the hottest stars
E. the blue feeling you get when you don't do well on an astronomy exam
Answer:
C. the blue colour of the Earth's sky
Explanation:
The Pleiades is a cluster of sister stars that are among the closest star cluster to earth.
The reflection nebula of the Pleiades is due to the scattering of the blue light from the hot blue luminous stars that dominate the star cluster. Th blue light is scattered from dust molecules, thought to be predominantly carbon compound like diamond dusts, and other compounds like iron.
The blue colour of the Earth's sky is the closest terrestrial phenomenon to the reflection nebula. On a clear cloudless day, molecules in the air scatter the blue component of light more than the other component colours of white light, giving the sky its characteristic blue coluor.
The common characteristics of the luminous nebula and the Earth's blue sky is that they both have their light scattered by the presence of small particles.
A man can walk three blocks east and four blocks north in 20 min. He can drive 12 times that distance in the same amount of time. How far can the man
drive in 20 min? Assume that each block is 0.3 kilometers.
Answer: 25.2 km
Explanation:
3 blocks east and four blocks east = 7 blocks
1 block = 0.3 km --> 7 blocks = 2.1 km
12 times 2.1 km = 25.2 km
Q- A body is acted upon by two forces 30N due east and 40N due North. Calculate
resultant and its direction.
Answer:
the following image will make you understand
Explanation:
if spiderman runs and jumps horizontally from the top of a 200m high building, what does he need his velocity to be to land on a building 100m high, 10m away from him?
Answer:
v = 2.22 m/s
Explanation:
First we apply the second equation of motion to the vertical motion of the body:
s = Vi t + (1/2)gt²
where,
s = y = vertical distance covered = 200 m - 100 m = 100 m
Vi = V₀y = Vertical Component of Initial Velocity = 0 m/s (because spider man jumps horizontally, thus his velocity has no vertical component initially)
t = Time Taken to Land on 100 m high building = ?
g = 9.8 m/s²
Therefore,
100 m = (0 m/s)t + (0.5)(9.8 m/s²)t²
t² = (100 m)/(4.9 m/s²)
t = √(20.4 s²)
t = 4.5 s
Now, we analyze the horizontal motion. Neglecting air friction, the horizontal motion is uniform with uniform velocity. Therefore,
s = vt
where,
s = x = horizontal distance covered = 10 m
v = V₀ₓ = Horizontal Component of Initial Velocity = Initial Velocity = ?
Therefore,
10 m = v(4.5 s)
v = 10 m/4.5 s
v = 2.22 m/s
How far away from the surface of earth does the acceleration due to gravity will be inclined by 36% of its value on the surface of earth? Radius of earth is 6400 km
Answer:
1,600 km
Explanation:
since the acceleration due to gravity reduces by 36%, it means that (1 - 36%) of acceleration still remains:
g' = 64g/100
using the acceleration formula:
g' = g x [R² / (R + height)²]
64g/100 = g x [R² / (R + height)²]
64/100 = R² / (R + height)²
√(64/100) = √[R² / (R + height)²]
8/10 = R / (R + height)
8 (R + height) = 10R
8R + 8height = 10R
8height = 2R
height = 2R / 8 = R / 4
R = 6,400 km
height = 6,400 km / 4 = 1,600 km
Answer:
The acceleration due to gravity will be inclined 1600 KM by 36% of its value on the surface of earthHURRY!!!!
Fred and Ted are racing cars down a frictionless track with a jump at the bottom
when suddenly an argument breaks out. Fred says, “If we release the cars from a
point twice as high as we are currently doing so, the cars will have twice the
gravitational potential energy, and therefore be travelling twice fast when they hit
the jump." Ted says, “In order to double the speed of the cars when they hit the
ramp, I think we will have to more than double the height!" Who is right? Prove it!
Answer:
Ted is correct
Explanation:
The equation for gravitational potential energy is PE = m·g·h
The equation for gravitational kinetic energy is KE = 1/2·m·v²
Where:
m = Mass of the object (The racing car)
g = Acceleration due to gravity
h = The height to which the object is raised
v = Velocity of motion of the object
From the principle of conservation of energy, energy can neither be created nor destroyed but changes from one form to another, we have;
Potential energy gained from location at height h = Kinetic energy gained as the object moves down the level ground
m·g·h = 1/2·m·v² canceling like terms gives
g·h = 1/2·v²
v = (√2·g·h)
If the speed is doubled, we have
2·v = 2× (√2·g·h) = (√2·g·4·h)
Therefore, if 2·v = v₂ then v₂ = (√2·g·4·h)
Since g, the acceleration due to gravity, is constant, it means that the initial height must be multiplied or increased 4 times to get the new height, that is we have;
v₂ = (√2·g·4·h) = (√2·g·h₂)
Where:
4·h = h₂
Which gives;
v₂² = 2·g·h₂
1/2·v₂² = g·h₂
1/2·m·v₂² = m·g·h₂ Just like in the first relation
Therefore, Ted is correct s they need to go up four times the initial height to double the speed.
The center of a bar magnet whose magnetic dipole moment is <6,0,0> A·m2 is located at the origin. A second bar magnet whose magnetic dipole moment is <7, 0, 0> A·m2 is located at 0.23 m. What is the vector force on the second magnet due to the first magnet? (Express your answer in vector form.)
Complete Question
The complete question is shown on the first uploaded image
Answer:
The force is [tex]\= F = (-0.001089, 0 ,0)[/tex]
Explanation:
From the question we are told that
The magnetic dipole moment of first magnet is [tex]z_1 = (6,0,0) A \cdot m^2[/tex]
The magnetic dipole moment of second magnet is [tex]z_2 = (7,0,0) A \cdot m^2[/tex]
The location of the second magnetic dipole moment is [tex]x = 0.39 \ m[/tex]
Generally the vector force on the second magnet due to the first is mathematically evaluated as
[tex]\= F =- \frac{\mu_o }{4 \pi} * \frac{6 * z_1 * z_2}{x^4}[/tex]
Where [tex]\mu _o[/tex] is the permeability of free space with value [tex]4\pi * 10^{-7} N/A^2[/tex]
substituting values
[tex]\= F = - \frac{ 4\pi * 10^{-7} }{4 \pi} * \frac{6 * 6 * 7}{0.39^4}[/tex]
[tex]\= F = (-0.001089, 0 ,0)[/tex]
Note the negative sign show that the force is an attraction force
A gas occupies a volume of 1.0 m3 in a cylinder at a pressure of 120kPa. A piston compresses the gas until the volume is 0.25m3, the temperature remaining constant. What is the new pressure of the gas?
Answer:
Approximately [tex]480\; \rm kPa[/tex], assuming that this gas is an ideal gas.
Explanation:
Let [tex]V(\text{Initial})[/tex] and [tex]P(\text{Initial})[/tex] denote the volume and pressure of this gas before the compression. Let [tex]V(\text{Final})[/tex] and [tex]P(\text{Final})[/tex] denote the volume and pressure of this gas after the compression.By Boyle's Law, the pressure of a sealed ideal gas at constant temperature will be inversely proportional to its volume. Assume that this gas is ideal. By this ideal gas law:
[tex]\displaystyle \frac{P(\text{Final})}{P(\text{Initial})} = \frac{V(\text{Initial})}{V(\text{Final})}[/tex].
Note that in Boyle's Law, [tex]P[/tex] is inversely proportional to [tex]V[/tex]. Therefore, on the two sides of this equation, "final" and "initial" are on different sides of the fraction bar.
For this particular question:
[tex]V(\text{initial}) = 1.0\; \rm m^3[/tex].[tex]P(\text{Initial}) = 120\; \rm kPa[/tex].[tex]V(\text{final}) = 0.25\; \rm m^3[/tex].The pressure after compression, [tex]P(\text{Final})[/tex], needs to be found.Rearrange the equation to obtain:
[tex]\displaystyle P(\text{Final}) = \frac{V(\text{Initial})}{V(\text{Final})} \cdot P(\text{Initial})[/tex].
Before doing any calculation, think whether the pressure of this gas will go up or down. Since the gas is compressed, collisions between its particles and the container will become more frequent. Hence, the pressure of this gas should increase.
[tex]\begin{aligned}P(\text{Final}) &= \frac{V(\text{Initial})}{V(\text{Final})} \cdot P(\text{Initial})\\ &= \frac{1.0\; \rm m^{3}}{0.25\; \rm m^{3}} \times 120\; \rm kPa = 480\; \rm kPa\end{aligned}[/tex].
A car travels 500m in 50s, then 1,500m in 75s. Calculate its averages speed for the whole journey
Answer:
15m/s
Explanation:
500 ÷ 50 = 10m/s
1500 ÷ 75 = 20m/s
10 + 20 = 30
30 ÷ 2 = 15m/s
Answer: 16 miles per second
Explanation:
Find the total distance traveled and the total time.
[tex]\text{average rate}=\dfrac{1500+500}{75+50}=\dfrac{2000\ miles}{125\ second}=\large\boxed{16\ mps}[/tex]
If It took 40 Seconds for a vehicle of weight 40,000 Newton to move round a 7 metres, What time will it achieve same feat for another circular path Of radius 21 metres given the Condition of the vehicle remains the same.
Answer:
t = 376.99 s
Explanation:
We must solve this problem with the equations and kinematics, let's start by looking for the speed of the vehicle,
v = d / t
v = 7/40
v = 0.175 m / s
Since the speed e remains constant, we must find the length of the circle is
L = 2π r
L = 2π 21
L = 131.95 m
In the problem it does not specify clearly, but in general the curves of the road correspond to half a circle, so the length of the road is
L ’= L / 2
L ’= 131.95 / 2 = 65.97 m
as the speed is constant
t = L ’/ v
t = 65.97 / 0.175
t = 376.99 s
A man weighing 80kg is standing on a trolley weighing
320kg. The trolley resting on smooth horizontal rails. If
the man starts walking on the trolley along the rails with
a speed of 1ms", then his displacement relative to the
ground after 4 second is
1) 4.8 m 2) 4 m 3) 3.2 m 4) 2.8 m
Answer:
Net displacement = 3.2 m
Explanation:
Given:
Mass of man = 80 kg
Mass of trolley = 320 kg
Speed = 1 m/s
Time = 4 sec
Computation:
Displacement by man = 1 m/s × 4 sec
Displacement by man = 4 m
Net ext force (trolley) = com at rest
So,
320 × X = 80(4 - X)
32X = 32 - 8X
40X = 32
X = 0.8 m
Net displacement = 4 m - 0.8 m
Net displacement = 3.2 m
Answer:
3) 3.2 m
Explanation:
The computation of the displacement relative to the ground after 4 seconds is shown below:
Let us assume the following
Starting x coordinate is at the origin
As it does not involve any external force so x coordinated would remain unchanged
Now the separation between the man and the trolley is
[tex]= 4 \times 1[/tex]
= 4 m
And, we assume the displacement of man be x
So, for trolley it would be (4 -x)
Now we develop the equation which is
[tex]80 \times x = 320 \times (4 - x)[/tex]
x = 16 - 4x
Therefore x = 3.2 m
a body starts from rest and gains the velocity of 5 metre per second into second is it of uniform velocity explain
Answer:
It is not a uniform velocity, because his velocity increases for 5 m every second (acceleration = 5m/s2), meaning his velocity always changes.
When he starts at rest, his velocity is 0 m/s. But in 1 second later, his velocity is already 5m/s. At 2 seconds, his velocity will be 10 m/s.
Un resorte se alarga 5 cm bajo la acción de una fuerza de 39,2 N. ¿Cuál es la constante del resorte? Si ahora la fuerza es 68,6 N. ¿Cuál es el nuevo alargamiento?
Answer:
[tex]k=784 N/m[/tex]
[tex]\Delta x=8,8 cm[/tex]
Explanation:
Usando la ley de Hook tenemos:
[tex]F=k\Delta x[/tex]
Solving it for k we have:
[tex]k=\frac{F}{\Delta x}[/tex]
[tex]k=\frac{39,2}{0,05}[/tex]
[tex]k=784 N/m[/tex]
Usando la misma ecuación y sabiendo k tenemos:
[tex]\Delta x=\frac{F}{k}[/tex]
[tex]\Delta x=\frac{68,6}{784}[/tex]
[tex]\Delta x=8,8 cm[/tex]
Espero esto te ayude!
Before beginning an experiment, Mrs. Wilson warns her science class not to drop the bar magnets on the floor. What is the most likely reason for Mrs. Wilson’s warning?
Answer:
we should not drop a magnet on the floor because the magnets tend to lose magnetism gradually and become weak over a period of time if they are not stored properly.
Answer:
Well depending on the floor like say if it was a wooden floor the magnet might lose it magnetism, if concrete floor the magnetic brake and still lose it magnetism, if a metal floor the magnet would stick not sure if it wood lose it magnetism or not but the possibilities still there, basically what I'm saying is the magnet would lose its magnetism if it were to interact with the floor maybe temporary or maybe permanently.
for those with with a learning disability it's a
Explanation:
The count rate of a radioactive source decreases from 1600 counts per minute to 400 counts per minute in 12 hours. What is the half-life of the source?
Answer:
[tex]t_{1/2}=6 h[/tex]
Explanation:
Let's use the decay equation.
[tex]A=A_{0}e^{-\lambda t}[/tex]
Where:
A is the activity at t timeA₀ is the initial activityλ is the decay constantWe know that [tex]\lambda=\frac{ln(2)}{t_{1/2}}[/tex]
So we have:
[tex]\lambda=\frac{ln(A/A_{0})}{t}[/tex]
[tex]\frac{ln(2)}{t_{1/2}}=\frac{ln(A/A_{0})}{t}[/tex]
[tex]t_{1/2}=\frac{t*ln(2)}{ln(A/A_{0})}[/tex]
[tex]t_{1/2}=6 h[/tex]
Therefore, the half-life of the source is 6 hours.
I hope it helps you!
water is a nonpolar molecule true or false
Answer:
Water is non-polar molecule False
Water is polar molecule because the electronegativity of Oxygen is much greater than electronegativity of hydrogen and it has also a bend shape that is why it is polar molecule.
Explanation:
I hope this will help you :)
False. Water is a polar molecule.
About waterWater (H2O) consists of two hydrogen atoms and one oxygen atom. The oxygen atom has a higher electronegativity, meaning it attracts electrons more strongly than hydrogen.
As a result, the shared electrons in the covalent bonds between hydrogen and oxygen are pulled closer to the oxygen atom, creating an uneven distribution of charge.
This leads to a partial negative charge (δ-) on the oxygen atom and partial positive charges (δ+) on the hydrogen atoms, making water a polar molecule.
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