3 years ago

A rock hits the ground with a speed of 7 m/s and a kinetic energy of 100 J. What is the rock's mass?

Physics

2 answers:

ad-work [718]3 years ago

8 0

Mass = (2*KE) / v²
∴ the answer is 200/49

Sloan [31]3 years ago

8 0

KE=1/2 times mass times velocity squared. So in this situation your equation would look like this 100J=1/2 times mass times 7 m/s^2. Your answer would be 4.0812 kg

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