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3 years ago

2. A car with mass 2,500 kg is travelling at 15 m/s. What is the car's kinetic energy?

Physics

1 answer:

BabaBlast [244]3 years ago

7 0

Answer:

c, 280,000J

Explanation:

You should use the equation KE (Kinetic Energy) = $\frac{1}{2} mv^2$

m = 2500

v = 15

KE = $\frac{1}{2} * 2500 * (15)^2\\$

KE = 281250 Joules.

This is consistent with the answer B, as all of the parameters given to you are rounded to 2 significant figures so naturally, the answer should also be rounded to 2 sig figs.

KE = 280,000 J

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