A body of mass 10 kg moving with velocity 10 m/s collides with a stationary body of mass 5 kg. After collision both bodies stick to each other, velocity of the joint body after collision is:

Question

A body of mass 10 kg moving with velocity 10 m/s collides with a stationary body of mass 5 kg. After collision both bodies stick to each other, velocity of the joint body after collision is: (A)  (3/10) m/s  (B)  20 m/s  (C)  (20/3) m/s  (D)  15 m/s

Tardigrade Admin · Accepted Answer

In an inelastic collision, linear momentum is conserved.
Since, in given collision the two bodies stick to each other, so collision is inelastic.
Applying conservation of linear momentum.

m_{1} v_{1} + m_{2} v_{2} = (m_{1} + m_{2}) v

..(i)
where

v

is the velocity of joint body.
Given,

m_{1} = 10 k g, v_{1} = 10 m / s, m_{2} = 5 k g

,

v_{2} = 0

. Substituting the values in Eq. (i), we get

10 \times 10 + 5 \times 0 = (10 + 5) v

or

100 = 15 v

or

v = \frac{100}{15} = \frac{20}{3} m / s

Q. A body of mass $10 k g$ moving with velocity $10 m / s$ collides with a stationary body of mass $5 k g$ . After collision both bodies stick to each other, velocity of the joint body after collision is:

$\frac{3}{10} m / s$

$20 m / s$

$\frac{20}{3} m / s$

$15 m / s$

Q. A body of mass 10kg moving with velocity 10m/s collides with a stationary body of mass 5kg. After collision both bodies stick to each other, velocity of the joint body after collision is:

103​m/s

20m/s

320​m/s

15m/s

Q. A body of mass $10 k g$ moving with velocity $10 m / s$ collides with a stationary body of mass $5 k g$ . After collision both bodies stick to each other, velocity of the joint body after collision is:

$\frac{3}{10} m / s$

$20 m / s$

$\frac{20}{3} m / s$

$15 m / s$