# physics

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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

• physics -

doubling speed makes energy increase by 2^2.
so 8*4=32J

• physics -

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.

• physics -

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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