An object of mass 1. 5 kg is lifted to a height of 2 m by a man who imparts a constant force of 100n.find work done by gravity in process.(answer isn't 200j or 30j)

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Solution

The work done by gravity is given by
w= mgh
so w= 1.5102=30

but motion of the stone is opposite to g so work is negative
so w=-30j

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An object of mass 1. 5 kg is lifted to a height of 2 m by a man who imparts a constant force of 100n.find work done by gravity in process.(answer isn't 200j or 30j)

The work done by gravity is given by w= m*g*h so w= 1.5*10*2=30 but motion of the stone is opposite to g so work is negative so w=-30j

The work done by gravity is given by
w= mgh
so w= 1.5102=30

but motion of the stone is opposite to g so work is negative
so w=-30j