Question

a bomb of mass 20 kg at rest explodes into two pieces of 8 kg and 12 kg the velocity of 8 kg mass is 5​

Answer 1

$\huge\underline{\underline{\bf \orange{Question-}}}$

A bomb of mass 20 kg at rest explodes into two pieces of 8 kg and 12 kg the velocity of 8 kg mass is 5m/s . Find kinetic energy of Larger Fragment.

$\huge\underline{\underline{\bf \orange{Solution}}}$

$\sf{Given}\begin{cases}{\sf Mass(M)=20kg}\\{\sf It\:explodes\:in\:2\:pieces}\\{\sf of\:mass(m_1)=8kg\:ans\:m_2=12kg}\\{Velocity\: of\:mass\:8kg\:(v_1)=5m/s}\end{cases}$

$\sf{To\:Find}\begin{cases}{\sf Kinetic\: Energy\: of\: larger\: Fragment}\end{cases}$

✏ Conservation Of Momentum

❏$\large{\boxed{\bf \blue{Mu=m_1v_1+m_2v_2} }}$

Initially Mass 20kg was at rest i.e u = 0m/s

$\implies{\sf 20×0=8×5+12v_2 }$

$\implies{\sf 0=40+12v_2}$

$\implies{\sf 12v_2=-40 }$

$\implies{\sf v_2=\dfrac{-40}{12}}$

$\implies{\bf \red{v_2=-3.3m/s}}$

✏ Kinetic Energy of Larger Fragment

$\large{\boxed{\bf \blue{K=\dfrac{1}{2}m_2v_2^2} }}$

$\implies{\sf K=\dfrac{1}{2}×12×(-3.3)^2 }$

$\implies{\bf \red{K=65.3J}}$

$\huge\underline{\underline{\bf \orange{Answer-}}}$

Kinetic Energy of Larger Fragment is ${\bf \red{65.3J}}$.