Question

A 0.1 kg object moving initially with a velocity of +0.2 m/s makes an elastic head-on collision with a 0.15 kg object initially at rest. What is the final velocity of the 0.1 kg object after the collision?

Answer 1

Answer:

v₁=0.2 ms

Explanation:

Given that

m₁ = 0.1 kg

u₁ = 0.2 m/s

m₂ = 0.15 kg

u₂ = 0 m/s

Lets take the final speed of the 0.1 kg ball = v₁

Lets take the final speed of the 0.15 kg ball = v₂

Given that collision is elastic that is why e = 1

$e=\dfrac{v_2-v_1}{u_1-u_2}$

$1=\dfrac{v_2-v_1}{u_1-u_2}$

u₁  - u₂  = v₁  - v₂

0.2 - 0 = v₁  - v₂

v₁  - v₂ = 0.2       ------------1

If there is no any external force on the system  then the total linear momentum of the system will be conserve.

m₁u₁ + m₂ u₂ =m₂ v₂ +m₁v₁

0.2 x 0.1 + 0 = 0.15 v₂  + 0.1 v₁

0.02 = 0.1 v₁ + 0.15 v₂

2 = 10 v₁   +  15 v₂     ----------------2

By using equation 1 and 2

We can say that

v₁=0.2 ms

v₂ =0 m/s