How Do You Calculate Kinetic Energy in AP Physics Problems?

AI Thread Summary
To calculate kinetic energy in AP Physics, it's essential to understand the conservation of energy principle, where potential energy at the height converts to kinetic energy just before impact. For a 3.00 kg toy falling from 10.0 m, the potential energy can be calculated using the formula PE = mgh, where g is the acceleration due to gravity (9.81 m/s²). This potential energy at the height is equal to the kinetic energy just before hitting the ground, allowing you to find the kinetic energy using KE = 1/2 mv². The key is recognizing that all potential energy transforms into kinetic energy when air resistance is disregarded. Understanding these concepts and equations will help solve similar problems effectively.
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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 don't not understand energy kientic or potential . I also don't 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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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.
 
But how do you get the initial and final energy. I am confused.
 
Your textbook should describe how to calculate the gravitational potential energy and kinetic energy.
 
Thats what I am confused on how do u find initial or final of whatever energy
 
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