Power Calculation for Car Accelerating on Inclined Road: Find Net Power [SOLVED]

[dgoudie]

[SOLVED] Power Problem

Homework Statement

A car (m = 760 kg accelerates uniformly from rest up an inclined road which rises uniformly, to a height, h = 45 m. Find the net power the engine must deliver to reach a speed of 25.1 m/s at the top of the hill in 20.7s (NEGLECT frictional losses: air and rolling, ...)
http://capaserv.physics.mun.ca/msuphysicslib/Graphics/Gtype12/prob28_1010caraccelpower.gif

Homework Equations

P=W/T

The Attempt at a Solution

I tried to get through this but the computer said i had the wrong answer. Here's the hint it gave me:
Hint: Don't forget that the car has a non-zero speed at the top of the hill. Use conservation of energy, what is the total energy of the car at the top of the hill?

Most of this assignment has been on Work energy theorem. If anyone could give me a direction to go would be greatly appreciated

 

[dgoudie]

So use$$\sum$$W = ef -ei?

Is the initial energy =0?

and Grav potential, is that mgh?Alright nevermind i got it. thanks a lot!