Velocity of the car as a function of time

AI Thread Summary
The discussion revolves around deriving the velocity of a car as a function of time when accelerated by a constant power of 135 kW. It is established that the velocity can be expressed as v(t) = sqrt(2Pt/m), where m is the mass of the car. Participants express confusion regarding the role of mass and acceleration in the equation, questioning how energy from the supplied power translates into velocity. The conversation also touches on how the formula would change if the car had an initial velocity greater than zero. Understanding the energy supplied over time is crucial to grasping the relationship between power, mass, and velocity.
dan_and_sim
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Homework Statement


A car of mass m = 1250 kg is accelerated from rest by a constant power
P = 135 kW. The car is moving along a straight line.
Neglecting air resistance and friction, show that the velocity of the car
as a function of time is given by v(t) = sqrt 2Pt/m

then How would this change if the initial velocity was not equal to 0

Homework Equations


P=w/t
V=P/f



The Attempt at a Solution


Whats confusing me here is the sqrt and the m, i would of assumed that it should be ma as its v=P/f
 
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So a constant power is supplied. How much energy is supplied in a time t? Where does the energy from the power supplied go? If you know these, you should be able to get the required expression.
 
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