Question

If a ball of mass 1 kg rolls with a speed of 2 m/s toward another ball of mass 1.5 kg at rest, what would be their combined speed if they stick together after colliding?

Answer 1

Answer:

$V=0.8\;\;m/s$

Explanation:

Given,

Mass of first ball  $m_1=1\; kg$

Mass of second ball $m_2=1.5\;kg$

Initial speed of the first ball $u_1=2\;m/s$

The second ball is initially at rest. So,  by the conservation of momentum

$p_i=p_f\\m_1u_1+m_2u_2=(m_1+m_2)V\\1\times2+1.5\times0=(1+1.5)V\\V=0.8\;\;m/s$