physics
posted by eng .
if a particle has work of 8J and doubles its speed. how much work it has done? Can we still determine work in this problem without mass

doubling speed makes energy increase by 2^2.
so 8*4=32J 
Work must be done ON the particle to increase its speed. Doubling the spped increases the kinetic energy to 32 J. Thus 24 J of work was done ON the particle. The particle "did" 24 J of work.

When you start by saying the particle "has work of 8J" I assumed you meant that it already had a kinetic energy of 8 J. Work is not something that you "have". It is something that you DO.
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