If a man lifts a body from ground, work done by the gravitational force is

Positive

(\neq 1)

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Negative

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Zero

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One

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Solution

The correct option is B Negative

Work done, $W = F s c o s θ$
Here, F = Force, s = displacement and θ = Angle between force and displacement
Gravitational force acting on the body of mass m in downwards direction, F = mg
s=h(Since body is displaced to height h)
$θ = 180^{\circ}$ (Since body is lifted upwards, i.e., displacement is in the opposite direction of the gravitational force)
Now, work done by gravitational force,
$W = F h c o s 180^{\circ} \Rightarrow W = m g h (- 1) = - m g h$
Thus, the required work done is negative.
Hence, the correct answer is option (b).

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