Question 224: Work, Energy and Power & Circular Motion

Question

If a body looses half of its velocity on penetrating $3$ $cm$ in a wooden block, then how much will it penetrate more before coming to rest?

Accepted Answer

We know the work energy theorem, $W = \Delta K = FS$
For first penetration, by applying work energy theorem we get,
${1 \over 2}m{v^2} - {1 \over 2}m{\left( {{v \over 2}} ight)^2} = F 	imes 3\,\,...(i)$
For second penetration, by applying work energy theorem we get,
${1 \over 2}m{\left( {{v \over 2}} ight)^2} - 0 = F 	imes S\,...(ii)$
On dividing $(ii)$ by $(i)$
${{1/4} \over {3/4}} = S/3$
$	herefore$ $S = 1\,cm$

Answer

$1$ $cm$

Answer

$2$ $cm$

Answer

$3$ $cm$

Answer

$4$ $cm$

Work, Energy and Power & Circular Motion

If a body looses half of its velocity on penetrating 3 cm in a wooden block, then how much will it penetrate more before coming to rest?

Choose the correct answer: