Work,Power and Energy question.....please help???

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Yagyadutt Mishra (5432)

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Work done :- F.r ( Dot product of F and r )

r = a[cos(wt+x) i + sin(wt+x) j]
dr/dt = [- asin(wt+x) i + a cost(wt +x) j ].w

dr = [- asin(wt+x) i + a cost(wt +x) j ].w.dt ----------(1)

= W

F = -K[coswt i + sin wt j)
dr = [- asin(wt+x) i + a cost(wt +x) j ].w.dt
F.dr = akw [ sin(wt+x) .coswt - sinwt.cos(wt+x) ] . dt
F.dr = a.k.w [ sinx ] . dt

Now put this in the integeration ...

W =

Work done = a.k.w sinx ( 2pi/w)
Work done = 2.a.k.sinx ( answer ...it depends on the value of x ..)

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