Question

A particle of mass 10 kg suddenly breaks into two particles of mass 2kg an 8kg. If initially particle was at rest and after breaking 8kg
moves with 5m/s, then speed of 2kg will be​

Answer 1

Answer:

v = 20 m/s

Explanation:

Applying the law of conservation of momentum,

Initial Momentum = Final Momentum

(10)×0 = (8)×(5) + (2)×(v)

Therefore,

    v = 20 m/s

Its direction is opposite to that of 8kg

Answer 2

Given:

Initial mass of the particle (m) = 10 kg

Mass of particle 1 (m₁) = 2 kg

Mass of particle 2 (m₂) = 8 kg

Speed of particle 2 (v₂) = 5 m/s

To find:

The speed of the 2 kg particle

Calculation:

Initially particle is at rest. So the initial velocity of the particle will be zero

By applying law of conservation of momentum

    $mv=m_{1}v_{1}+ m_{2}v_{2}$

    $10\times0=(2\times v)+(8\times5)$

    $2v+40=0$

    $v=-20\ m/sec$

Final answer:

The speed of the 2 kg particle is  20 m/sec in the direction opposite to that of 8 kg particle