A ball is thrown vertically upwards, it reaches the height $h$ and then returns to the initial position. Work done by gravity when ball moves upwards is $W_{1}$ and $W_{2}$ when ball moves in downward direction. Then

W_{1} = m g h, W_{2} = m g h

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W_{1} = m g h, W_{2} = - m g h

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W_{1} = - m g h, W_{2} = m g h

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W_{1} = - m g h, W_{2} = - m g h

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Solution

The correct option is C $W_{1} = - m g h, W_{2} = m g h$
Let upward direction be the +ve $y$ -axis
Then gravity force $= - m g$
When ball moves upwards, displacement $d s = h$
$W_{1} = \to F . \to d s = - m g . h = - m g h$
Now, when ball move downwards, displacement $d s = - h$
$\Rightarrow W_{2} = \to F . \to d s = (- m g) . (- h)$
$W_{2} = m g h$

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A ball is thrown vertically upwards, it reaches the height h and then returns to the initial position. Work done by gravity when ball moves upwards is W1 and W2 when ball moves in downward direction. Then

The correct option is C W1=−mgh,W2=mghLet upward direction be the +ve y-axis Then gravity force =−mg When ball moves upwards, displacement ds=h W1=→F.→ds=−mg.h=−mgh Now, when ball move downwards, displacement ds=−h ⇒W2=→F.→ds=(−mg).(−h) W2=mgh

A ball is thrown vertically upwards, it reaches the height $h$ and then returns to the initial position. Work done by gravity when ball moves upwards is $W_{1}$ and $W_{2}$ when ball moves in downward direction. Then