Power and velocity physics homework

Thread starter ajmCane22
Start date Jun 2, 2011
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Homework Physics Physics homework Power Velocity

AI Thread Summary

To determine the power required to accelerate a 1600 kg SUV from 15.0 m/s to 40.0 m/s in 4.0 seconds, the change in kinetic energy must first be calculated using the formula ΔK = 1/2m(Vf^2 - Vi^2). The user expresses uncertainty about the available information for calculating power, noting the relationship P = W/t and W = F/d. The discussion confirms that the change in kinetic energy can be used to find the work done. Ultimately, the key focus is on applying the kinetic energy formula to derive the necessary power for the speed change.

Jun 2, 2011

ajmCane22

Homework Statement

What is the power needed to change the speed of a 1600 kg SUV from 15.0 m/s to 40.0 m/s in 4.0 seconds

The Attempt at a Solution

I know that P = W/t and W = F/d, but I feel like there is not enough info to use this equation. Am I missing something?

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Jun 2, 2011

ideasrule

Homework Helper

Can you calculate the change in the SUV's kinetic energy?

Jun 2, 2011

ajmCane22

Oh! So I would use \DeltaK = 1/2m(Vf^2-Vi^2)?

Jun 2, 2011

ideasrule

Homework Helper

Yes, that's the change in energy.

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