# AP Physics on Energy

#### Absolute Zero

Hello this is my first time posting on these forums:)
I have a question on one of my homework assigments it goes like this:
A 3.00 Kg toy falls from a height of 10.0 m Just before hitting the ground, what will be its kinetic energy? (Disregard Air Resistance. g=9.81
I have a problem with this because i dont not understand energy kientic or potential . I also dont know what equations there are or how to use them.
I hope you guys can teach me how do this problem and the concepts of energy:)

Thx:)

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#### Anthropic

Energy is conserved in a system. In this situation you have all potential energy at the top (10.0m) and all kinetic energy at the bottom right before the object hits the ground.

The potential energy is "converted" to kinetic energy. So your initial potential energy is = your final kinetic energy.

with these problems, remember to use your conversation of energy equations
initial potential energy + initial kinetic energy = final potential energy + final kinetic energy.

#### Absolute Zero

But how do you get the initial and final energy. Im confused.

#### Doc Al

Mentor
Your textbook should describe how to calculate the gravitational potential energy and kinetic energy.

#### Absolute Zero

Thats what im confused on how do u find initial or final of whatever energy

"AP Physics on Energy"

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