This should be an easy one: Work required to change speed

AI Thread Summary
To double the speed of an object with kinetic energy K, one must understand the work-kinetic energy theorem, which states that the work done equals the change in kinetic energy. Kinetic energy is proportional to the square of the speed, meaning if speed is doubled, the kinetic energy increases by a factor of four. Therefore, to determine the work required to achieve this change, one must calculate the difference between the final and initial kinetic energy. This involves using the formula for kinetic energy, K = 1/2 mv², where m is mass and v is speed. Understanding these principles will guide the calculation of the necessary work.
atrain77a
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Hi, I apologize for the simplicity here, I'm just getting started. Here's the question:

An object has kinetic energy, K. How much work do you have to do to double the speed of the object?

Any suggestion on how to start this would be much appreciated. :smile:
 
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The work-kinetic energy theorem states that the work done on a particle equals the change in kinetic energy of the particle. From that statement, you should have enough information to answer your question.
 
In order to use TALewis' hint, you will need to know how kinetic energy depends on speed.
 

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