# PHYSICS!!

posted by Allison

A car's engine can accelerate a car from rest to 30 m/s in 6 s. if the car's mass is 1300 kg, what is the power of the engine?

can someone give me the answer because i just want to verify it with my own?
thank you!

1. Allison

the answer i got is 288600W

2. bobpursley

power= work/time= 1/2 m v^2 / tune

I don't get that result.

3. Allison

can you tell me exactly what you did instead of just giving me the formula?

4. CANTIUS

To expand upon bobpursley's solution:
P = W/t =(1/2 m v^2)/t = (m v^2)/(2t)
m = 1300 kg, v = 30 m/s, t = 6 s
The work is equal to the change in kinetic energy, which, since it started from rest, is simply (1/2) m v^2
The formula given is the definition of power.

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