Inelastic Collision of Masses – Rankers Physics

Collision: Practice Problem & Solution

A moving body of mass $m$ and velocity $3\text{ km/hour}$ collides with a rest body of mass $2\text{ m}$ and sticks to it. Now the combined mass starts to move. What will be the combined velocity? (1996)
$3\text{ km/hour}$
$4\text{ km/hour}$
$1\text{ km/hour}$
$2\text{ km/hour}$

Short Solution (Best for NEET):

To solve this problem, we apply the core principles of Collision. Understanding the underlying formula is key to arriving at the correct answer below:

Using conservation of linear momentum, $mu_1 = (m+2m)v$, where $u_1 = 3\text{ km/hour}$. Solving gives $3m = 3mv \implies v = 1\text{ km/hour}$

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