A body falls towards earth in air. Will its total mechanical energy be conserved during the fall ? Justify.
A body falls towards earth in air. Will its total mechanical energy be conserved during the fall ? Justify.
No, because a small part of its energy is used against air resistive force which is nonconservative force. In this condition, gain in $\mathrm{KE}<$ loss in$ PE.$
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- [JEE MAIN 2013]
$A$ section of fixed smooth circular track of radius $R$ in vertical plane is shown in the figure. $A$ block is released from position $A$ and leaves the track at $B$. The radius of curvature of its trajectory when it just leaves the track at $B$ is:
$A$ section of fixed smooth circular track of radius $R$ in vertical plane is shown in the figure. $A$ block is released from position $A$ and leaves the track at $B$. The radius of curvature of its trajectory when it just leaves the track at $B$ is: