Form a hypothesis. Which will be greater, the potential energy of the car at the top of the ramp or the kinetic energy of the ca

Question

Neko [114]

3 years ago

11

Form a hypothesis. Which will be greater, the potential energy of the car at the top of the ramp or the kinetic energy of the ca

r at the bottom of the ramp

Physics

1 answer:

AleksandrR [38] · Answer 1 · 2022-02-19T21:57:41+03:00

The potential energy of the car at the top of the ramp is greater than the kinetic energy of the car at the bottom of the ramp

Explanation:

Here we have a car moving down along a ramp. In absence of force of friction, the total mechanical energy of the car while moving down would be conserved:

$E=PE+KE = const.$

where

PE is the potential energy

KE is the kinetic energy

However, this is not true if friction acts on the car. When the car is still at the top of the ramp, its speed is zero, so its kinetic energy is zero, and all the energy is just potential energy:

$E=PE$

While the car moves down along the ramp, friction does work on it, and part of the total mechanical energy is wasted and converted into thermal energy. As a result, the car reaches the bottom of the ramp with a final energy which is less than the initial energy:

$E'$

Also, at the bottom of the ramp, all the energy is just kinetic energy, since the height of the car is now zero, so

$E'=KE$