E=1/2mv^2 Given E and change in velocity

AI Thread Summary
To find the mass of the car using the work-energy principle, the equation E=1/2mv^2 is applied, where E represents the work done. The problem states that 185 kJ of work is required to accelerate the car from 23.0 m/s to 28.0 m/s. The correct approach involves calculating the change in kinetic energy, which is determined by the difference in kinetic energy at the two velocities. The user confirms that they arrived at the correct mass by applying the formula correctly. The discussion emphasizes the importance of understanding kinetic energy changes during acceleration.
LoganNagol
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Homework Statement


It takes 185 kJ of work to accelerate a car from 23.0 m/s to 28.0 m/s. What is the car’s mass?

Homework Equations


E=1/2mv^2

The Attempt at a Solution


I get that I must put (2E) over V2 I am just not sure if I was allowed to put the change in velocity so it would look like this. (2E)/(V12 - V02)
If it is correct will someone please tell me why?
 
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Why don't you calculate it and then check the kinetic energy of the car befoere and after the velocity change?
 
Thanks! I got the answer correct.
 

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