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प्रश्न
A body of mass m is moved from ground to a height h. If the force of gravity on mass of 1 kg is g newton, find the force needed to lift the body.
उत्तर
When a body of mass m at A on the ground is raised above ground through height h at B force is applied. This force applied = weight of body
Force on mass m = F = m g
Where ‘g’ is the force of gravity on a mass of 1 kg.
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