Kinetic Energy and Work Homework Help

AI Thread Summary
The discussion revolves around calculating the power supplied by a car's engine while merging onto a freeway, given its mass, initial and final speeds, work done, and average force. The key equations involved are power (P = W/T) and the need to determine the time (T) taken for the acceleration. A critical piece of information is the distance of 80 meters, which is necessary to calculate the time required for the speed change. Participants emphasize that this distance is essential to solve for the average power. Understanding the relationship between distance, speed, and time is crucial to completing the problem.
KTiaam
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Homework Statement



While merging onto a freeway, a 1900 kg car accelerates from 17 m/s to 33 m/s

What power did the engine supply?

W = 7.6 x 105 J
F = 9500 N

Homework Equations



P=W/T

The Attempt at a Solution



Not sure how to find T.
 
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KTiaam said:

Homework Statement



While merging onto a freeway, a 1900 kg car accelerates from 17 m/s to 33 m/s

What power did the engine supply?

W = 7.6 x 105 J
F = 9500 N

Homework Equations



P=W/T

The Attempt at a Solution



Not sure how to find T.

Is that the whole problem statement? Are you sure it didn't ask for the average power?
 
the previous questions were

a)

how much work was done?

which i found out was 7.6 x 105

b) If the velocity change took 80m of road what average force did the cars energy supply?

which i found out was 9500 N

that was all that was given to me
 
KTiaam said:
the previous questions were

a)

how much work was done?

which i found out was 7.6 x 105

b) If the velocity change took 80m of road what average force did the cars energy supply?

which i found out was 9500 N

that was all that was given to me

You left the 80m distance out of your original post. That is the piece of information that you need to figure out how long it took the car to accelerate from v1 to v2 in 80m distance...
 
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