A ball is moving to and fro about the lowest point $A$ of a smooth hemispherical bowl. If it is able to rise up to a height of $20 \,cm$ on either side of $A$, its speed at $A$ must be .......... $m/s$ (Take = $10 m/s^2$, mass of the body $5 \,g$)
A ball is moving to and fro about the lowest point $A$ of a smooth hemispherical bowl. If it is able to rise up to a height of $20 \,cm$ on either side of $A$, its speed at $A$ must be .......... $m/s$ (Take = $10 m/s^2$, mass of the body $5 \,g$)
$0.2 $
$2$
$4$
$4.5$
A ball is moving to and fro about the lowest point $A$ of a smooth hemispherical bowl. If it is able to rise up to a height of $20 \,cm$ on either side of $A$, its speed at $A$ must be .......... $m/s$ (Take = $10 m/s^2$, mass of the body $5 \,g$)
$v = \sqrt {2gh} = \sqrt {2 \times 10 \times 0.2} = 2\,m/s$