Answers
Answer:
okay
Explanation:
power is rate of doing work
power is workdone over time taken
but you don't have information concerning the force
Power = work/time
Work = force x distance
Force = mass x acceleration
So Power = (mass x acceleration x distance) / (time)
acceleration = 8m/s / 2sec = 4 m/s²
distance = (avg speed) x (time) = 8 m
time = 2 sec
we don't know the runner's mass
Power = (mass) x (4 m/s²) x (8 m) / (2 sec)
Power = (16 x mass in kg) watts
=============================================
Slightly easier way to do it:
Power = (runner's kinetic energy at the end) / (time)
Power = (1/2 m v²) / (time)
Power = (1/2 mass) (64 m²/s²) / (2 sec)
Power = (16 x runner's mass in kg) watts
Related Questions
State the conditionsfor tge equilibrium of a body which is acted upon by a number of forces
Answers
The anti clockwise moment should be equal to clockwise moment.
The resistance of a wire of length 100cm and diameter 0.3m is found to be 30 ohm's.calculate:(1) resistivity (2) conductivity (3) what length of the wire will produce 5 ohm's resistance.
Answers
Hi there!
1)
We can use the following equation to solve for resistivity.
[tex]R = \frac{\rho L}{A}[/tex]
R = Resistance (30 Ω)
ρ = Resistivity (? Ωm)
L = Length (100cm = 1 m)
A = Cross-sectional area of wire (r = 0.15m, A = πr², A = 0.0707 m²)
Rearrange the equation to solve for resistivity.
[tex]\rho = \frac{RA}{L}\\\\\rho = \frac{30 * 0.0707}{1} = \boxed{2.121 \Omega m}[/tex]
2)
The conductivity of a resistor is equivalent to:
[tex]\sigma = \frac{1}{\rho}[/tex]
σ = Conductivity (S/m)
ρ = Resistivity (2.121 Ωm)
Solve:
[tex]\sigma = \frac{1}{2.121} =\boxed{0.472 \frac{S}{m}}[/tex]
3)
We can use the equation for resistivity to solve. Rearrange the equation for length:
[tex]R = \frac{\rho L}{A}\\\\L = \frac{AR}{\rho}\\\\L = \frac{0.0707 * 5}{2.121} = \boxed{0.167 m}[/tex]
A proton travels at a velocity of 3.0x106 m/s in a direction perpendicular to a uniform magnetic field.
A proton entering a magnetic field
If the proton experiences a magnetic force of 1.15x10-13 N, what is the magnitude of the magnetic field?
Answers
Hi there!
Recall the equation for magnetic force on a moving particle.
[tex]F_B = qv \times B[/tex]
[tex]F_B[/tex] = Magnetic Force (N)
q = Charge of particle (C)
v = Velocity of particle (m/s)
B = Magnetic Field Strength (T)
**This is a cross product, so the equation can be written as [tex]F_B[/tex] = qvBsinφ where φ is the angle between the velocity vector and magnetic field vector.
Since the proton is traveling perpendicular to the field, we can disregard the cross product. (sin90 = 1.)
Rearrange the equation to solve for 'B':
[tex]B = \frac{F_B}{qv}\\\\B = \frac{1.15 * 10^{-13}}{(1.6 * 10^{-19})(3.0 * 10^6)} = \boxed{0.24 T}[/tex]
What is the energy required to start a chemical reaction called
Answers
One of the basic rules of science is
that it can change if new information is discovered.
Use what you know about the solar system, how has the geocentric
model of the solar system changed over time?
A. Jupiter is no longer at the center
B. a black hole is no longer at the center
C. the Earth is no longer at the center
D. the Sun is no longer at the center
Answers
So answer is C - the earth in no longer believed to be the center of the solar system
Charges are pushed through an electric circuit by?
Answers
Conducting an experiment without a theory, assumptions, or expectations can lead to what issue?
Answers
Answer:
When accounting for threats to validity in their study design, researchers must make assumptions about their environment. If any of these assumptions prove to be false, then it is more difficult to properly interpret the results of the experiment.
Explanation:
How does carbon dioxide behave as a greenhouse gas?
Answers
Answer:
Carbon Dioxide is supposed to block out radiation and is can be used in plant to make material, include cement,plastic,and rubber. However, since carbon dioxide is a greenhouse gas, it warms the Earth,and causes the climate to change.
(Hope This Helps <3)
How much work would I do if I pushed an object with a force of 64 a distance of 11 m
Answers
Answer:
Work=Force×distance
Explanation:
work=force×distance
force=64N
distance=11m
work=64×11=704Joules
Remember unit of work is Joules or Newton metre(N/m).
In a skate park, you are trying to determine how to get the most speed at the bottom of the ramp. If the ramp is 4.5 m high, and you start at the top of the ramp with an initial velocity of 1.5m/s, how fast will you be rolling at the bottom of the ramp, given there is no friction. Use conservation of energy to solve.
Answers
Answer:
If you have an initial velocity of 1.5m/s and the ramp height is 4.5, and an extreme fart is initiated at the bottom of the ramp exerting an didditional upward force, and the smell of the fart causes you to begin flailing, and everyone running from you causes an additional wind force, then you would be rolling at a speed of 3 m/s given there is no friction. :)
What is the initial vertical velocity?
Answers
Answer:
Thus, any projectile that has an initial vertical velocity of 21.2 m/s and lands 10.0 m below its starting altitude spends 3.79 s in the air.The initial vertical velocity is the vertical component of the initial velocity: v 0 y = v 0 sin θ 0 = ( 30.0 m / s ) sin 45 ° = 21.2 m / s .
Question 7 of 32
What is a disadvantage of using nonrenewable energy resources?
A. They cause problems with bird populations.
O B. They do not produce greenhouse gases.
C. They cannot be replenished in a human lifetime.
D. They are readily available.
Answers
Answer:
I think the answer will be C
Explanation:
D doesnt make sense
A doesn't make sense
B nonrenewable resources do release greenhouse gasses
discuss how the nucleus is held together.
Answers
Answer:
the nucleus of an atom is held together by a strong nucleus force that binds together protons and neutrons.all though the strong nucleus force is stronger than the four fundamental forces.it acts over very short typically nucleus substances
true or false a solution containing 5 moles of solute per kilogram of solvent is said to he a 5 M concentrated solution
Answers
Answer:
False
that should be 5m
Explanation:
Moles of solute=5molMass of solvent in kg=1kgSo
Molality=5/1Molality=5m
How much energy is required to Melt 450g of Ice?
Answers
Answer:
The latent heat of fusion for water is 334 joules per gram.
Explanation: im smart
use scale drawing vector and find magnitude and direction of Sum of A+B
Answers
The magnitude of the sum of the two vectors is 20.22 m and the direction of the two vectors, A + B is 50⁰.
Magnitude of Sum of vector A+BThe magnitude of the sum of the two vectors is calculated as follows;
Bx = Bcosθ
By = Bsinθ
Bx = 15 m x cos(30) = 12.99 m
By = 15 x sin(30) = 7.5 m
Ax = 8 m x cos(90) = 0 m
Ay = 8 x sin(90) = 8 m
Ax + Bx = 0 + 12.99 m = 12.99 m
Ay + By = 8m + 7.5 m = 15.5 m
R = √12.99² + 15.5²
R = 20.22 m
Direction of the vectorstanθ = 15.5/12.99
tanθ = 1.19
θ = 50⁰
Learn more about addition of vectors here: https://brainly.com/question/2927458
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Use the following d/t graph to determine the velocity of the object
Answers
Answer:
1/3 m/s
Explanation:
Because the graph goes from 3 to 8 on the Y axis we know that each line is 0.5 and on the X axis each line is 1, Then, the slope , or velocity, is 1/3
see? This graph is kinda set up to throw you.
Is there a 1/3 option for this ??
What is the current if the electricpotential is 120 V and the resistance is
60 ohms?
Answers
Answer:
2 amperes
Explanation:
V = IR
V/R = I
120 v / 60 ohms = 2 amps
Which of the following statements is true.
a. Gravity is a force dependent on mass and force.
b. Gravity is a force dependent on mass and distance.
C. No Gravity is a force dependent on speed and force.
d. Gravity is a force dependent on force and distance.
Answers
B. Gravity is a force dependent on mass and Distance
A team of scientists is working to determine if a meteor created a landform. One team includes geologists
Which other branch of Earth science would these scientists most likely represent?
O astronomy
O meteorology
O oceanography
O environmental science
Answers
Answer:
your answer should be astronomy
Explanation:
waves in a pond or lake are
Answers
True or false: When your ear detects sound, there is an actual collision of particles from the sound wave that hit your ear drum
Answers
Answer:
True: For a sound wave to propagate, air particles must be displaced in the direction of propagation - it is the displacement of these particles that causes the eardrum to vibrate and recognize the sound.
The speed of light is 3 x 108 m/s (300,000,000 m/s). A light wave has a wavelength of 400 nm (0.0000004 m). What is the frequency of the light
wave?
Answers
Explanation:
velocity = wavelength × frequency
3×10⁸ = 400/10⁹ × frequency
frequency = 3 × 10¹⁵ /400
frequency = 75×10¹¹Hz
Why does the moon block the Sun during a solar eclipse
Answers
Answer:
In a solar eclipse, the sun is completely blocked because the moon moves between the earth and the sun. Although the moon is much smaller than the sun because it is located so far away from the earth, the moon can completely block sunlight from the earth's point of view.
Which TWO types of waves can transmit energy through a vacuum?
A.) radio waves
B.) seismic waves
C.) sound waves
D.) water waves
E.) x-rays
Answers
Answer:
Answer = Radio waves and X-rays
Explanation:
Hope that helps! :)
what force is required to move 7m if the work done is 9j
Answers
Answer:
Work = force x displacement
Force = W/s = 9/7 = 1.28 N
PLSS HELP AND I WILL GIVE BRAINLY TO THE ONE WHO ANSWERS CORRECTLY
60 J of work is needed to move a charge of 5 C through a wire.
1. What potential difference will do this work?
2. What is the electric current if this charge moves through a wire over time of 1.25 seconds?
3. How long will it take to move 60 C of charge?
4. What is the resistance in the circuit?
5. If the resistance doubles, what will be the new electric current?
Answers
The potential difference,electric current ,resistance and new electric current will be 12 V,4 A,3 Ω,2 A.
What is resistance?Resistance is a type of opposition force due to which the flow of current is reduced in the material or wire. Resistance is the enemy of the flow of current.
The energy in terms of the charge and potential difference is;
E= qV
60=5 C × V
V= 12 V
The electric current is found as;
[tex]\rm I= \frac{q}{t} \\\\ I= \frac{5}{1.25}\\\\ I=4 \ A[/tex]
From the ohm's law;
V=IR
12=4 ×R
R=3Ω
If the voltage is constant and the resistance is doubled, then the new electric current is half of the previous condition;
[tex]\rm I'=\frac{I}{2} \\\\ I'=\frac{4}{2} \\\\\ I'=2 \ A[/tex]
Hence, the potential difference,electric current ,resistance and new electric current will be 12 V,4 A,3 Ω,2 A.
To learn more about the resistance, refer to the link;
https://brainly.com/question/20708652
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Show work for either one thanks
Answers
The maximum velocity of the pendulum is determined as 3.03 m/s.
Maximum velocity of the pendulum
The maximum velocity of the pendulum is calculated from the principle of conservation of energy as shown below;
K.E = P.E
¹/₂mv² = mgh
v² = 2gh
v = √2gh
where;
h is the maximum height = 0.468 mv is the maximum velocityv = √(2 x 9.8 x 0.468)
v = 3.03 m/s
Thus, the maximum velocity of the pendulum is determined as 3.03 m/s.
Learn more about maximum velocity here: https://brainly.com/question/20595261
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what is linear momemtum
Answers
Answer:
Its momentum thats linear
Explanation:
from my secret analysis i would say this is really linear
If a neighbor pushes a lawnmower six times as far as you do but exerts only one third the force, which one of you does more work and by how much?
Answers
Answer:
Your neighbor does twice as much work.
Explanation:
Distance(measurement) * exertion(force of pushing mower) = work
6 * 1/3 = 2
Your neighbor does twice as much work as you do.
W= 3F.d
Explanation:
You
W= F.d
W= F.d
Your neighbor
W= (1/2 F) (6d)
W= 6/2 F.d
W= 3 F.d