A 3 kg mass is moving with an initial velocity of 10 m/s. The mass collides with a 5 kg mass, which is initially at rest. What is the final velocity of the masses after the collision if it is perfectly inelastic?

2 Answers
Jun 11, 2017

The ultimate velocity will be #3.75ms^-1#.

Explanation:

According to Newton's law of momentum,
#3×10+5×0=(3+5)v# where v is ultimate velocity.
Hence,
#v=3.75ms^-1#

3.75 m/s

Explanation:

Inelastic collisions are those which lose the most kinetic energy in the process.

From the initial fromula:

#m_1v_1=(m_1+m_2)*v_2#

...we can turn it into this more directly:

#v_2=m_1 / (m_1 + m_2)*v_1#

#v_2= 3/ (3+5) * 10 = 30/8 = 3.75m/s #