What is the average power in accelerating this car

AI Thread Summary
To calculate the average power of a 1,000 kg car accelerating from rest to 25.0 m/s in 7.50 seconds, the total work done can be determined by the change in kinetic energy. The formula for average power is total work divided by the time interval. Since acceleration is not needed for this calculation, focus on the kinetic energy change to find the work done. The average power can then be derived from this work over the given time. Understanding these concepts is essential for solving similar physics problems effectively.
Groovy_Duck
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I was given this as a practice problem:

A 1,000 kg car accelerates from rest to 25.0 m/s in 7.50 s. What is the Average power?

So far, I know that P= FD/t F=ma
m=1000kg
initial velocity = 0
final velocity = 25.0 m/s
t = 7.50 s

how do I find the acceleration? thx
 
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The acceleration is \frac{{dv}}{{dt}}, the change in velocity over the change in time
 
Groovy_Duck said:
I was given this as a practice problem:

A 1,000 kg car accelerates from rest to 25.0 m/s in 7.50 s. What is the Average power?

So far, I know that P= FD/t F=ma
m=1000kg
initial velocity = 0
final velocity = 25.0 m/s
t = 7.50 s

how do I find the acceleration? thx

You don't have to find the acceleration. Average power is (total work done over a time interval) divided by the time interval.

Total work done can be calculated by the change in kinetic energy of the car.
 
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