A trolley weighing 40 kg moves along the rails at a speed of 1 m / s. A man weighing 60 kg runs towards

A trolley weighing 40 kg moves along the rails at a speed of 1 m / s. A man weighing 60 kg runs towards her at a speed of 0.5 m / s. Determine the speed of the cart after the person jumps into it.

Given:

m1 = 40 kg – trolley weight;

v1 = 1 m / s – trolley speed;

m2 = 60 kg – human weight;

v2 = 0.5 m / s – human speed.

It is required to find v3 – the speed of the cart after a person jumps into it.

According to the law of conservation of momentum:

m1 * v1 – m2 * v2 = (m1 + m2) * v3

40 * 1 – 60 * 0.5 = 100 * v3

40 – 30 = 100 * v3 or from here:

v3 = 10/100 = 0.1 m / s.

Answer: the trolley speed will be 0.1 m / s.