Question

Two identical bodies are sliding toward each other on a frictionless surface. One moves at 1 m/s and the other at 2 m/s. They collide and stick. The speed of the combined mass is

Answer 1

Answer:

$V=\dfrac{3}{2}\ m/s$

Explanation:

Two identical bodies are sliding toward each other on a frictionless surface.

Initial speed of body 1, m₁ = 1 m/s

Initial speed of body 2, m₂ = 2 m/s

They collide and stick.

We need to find the speed of the combined mass. Let V is the speed of the combined mass.

Using the conservation of momentum.

$m_1u_1+m_2u_2=V(m_1+m_2)$

We have, m₁ = m₂ = m

$m\times 1+m\times 2=(m+m)V\\\\m+2m=2m\times V\\\\3m=2mV\\\\V=\dfrac{3}{2}\ m/s$

So, the speed of the combined mass is $\dfrac{3}{2}\ m/s$.