Kinetic energy

Mar 2020
12
0
Brockton
Hello, I know this might seem easy to most people but I’m personally struggling in my physics class. My question states: A 0.05 kg car starts from rest at a height of 0.95m. Assuming no friction, what is the kinetic energy of the hill?(Assume g=9.81 m/s^2)
A.0.466 joules
B. 0.308 J
C. 4317 J
D. 0.0475 J
Also requires me to show work or a way of solving it. I’m lost on what equation to utilize to solve it or better yet how to solve it in general.
 
Last edited:
Jan 2019
106
80
Hello, I know this might seem easy to most people but I’m personally struggling in my physics class. My question states: A 0.05 kg car starts from rest at a height of 0.95m. Assuming no friction, what is the kinetic energy of the hill?(Assume g=9.81 m/s^2)
A.0.466 joules
B. 0.308 J
C. 4317 J
D. 0.0475 J
Also requires me to show work or a way of solving it
how does a hill have kinetic energy? maybe you should re-check the question statement again.
 
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topsquark

Forum Staff
Apr 2008
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On the dance floor, baby!
Hello, I know this might seem easy to most people but I’m personally struggling in my physics class. My question states: A 0.05 kg car starts from rest at a height of 0.95m. Assuming no friction, what is the kinetic energy of the hill?(Assume g=9.81 m/s^2)
A.0.466 joules
B. 0.308 J
C. 4317 J
D. 0.0475 J
Also requires me to show work or a way of solving it. I’m lost on what equation to utilize to solve it or better yet how to solve it in general.
Given the answer key I suspect you are looking for the gravitational potential energy of the car at the top of the hill?

-Dan
 
Mar 2020
12
0
Brockton
how does a hill have kinetic energy? maybe you should re-check the question statement again.
It won’t let me edit the comment but I meant to say “what is the kinetic energy of the car when it reaches the bottom of the hill”
 
Mar 2020
12
0
Brockton
Given the answer key I suspect you are looking for the gravitational potential energy of the car at the top of the hill?

-Dan
No it states what is the kinetic energy of the car when it reaches the bottom of the hill
 
Jan 2019
106
80
conservation of energy

gravitational potential energy at the top of the hill = kinetic energy at the bottom of the hill
 
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Mar 2020
12
0
Brockton
conservation of energy

gravitational potential energy at the top of the hill = kinetic energy at the bottom of the hill
Ok but since I’m looking for kinetic energy, how would I solve this without an indication of the velocity.
 
Jan 2019
106
80
what is the formula for gravitational potential energy?
 
Mar 2020
12
0
Brockton
what is the formula for gravitational potential energy?
Had to search this up ngl, but mass multiplied by G^2 multiplied by height. I went ahead and did the equation myself and got 4.57 which isn’t one of the options so I don’t know what I did wrong.
 
Mar 2020
12
0
Brockton
what is the formula for gravitational potential energy?
I also looked into it further and simply did Mass multiplied by height and got 0.0475J which is D on the answer sheet. Would that be correct?