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rosijanka [135]
3 years ago
14

An object has a kinetic energy of 810 J after falling a certain distance. If the mass of the object is 20kg, what is the speed o

f the object at this time?
I need the equation and answer please!
Physics
1 answer:
Darina [25.2K]3 years ago
6 0
Don't let the "falling" confuse you. A moving object's kinetic energy is

K.E. = 1/2 (mass) (speed^2)

no matter what direction it's moving, or why.

In this problem, you know the KE and the mass, so

810 J = 1/2 (20 kg) (speed^2).

I think you can probably find the speed now.
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Answer:

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Answer:

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