Question

Тележка массой 100кг катится со скоростью 5м/с Человек бежит навстречу со скоростью 8м/с и прыгает в неё. Какова масса человека если тележка остановилась

Answer 1

Ответ: 62.5 кг...................

Answer 2

Calculation of the Person's Mass

To determine the mass of the person, we can use the principle of conservation of momentum. According to this principle, the total momentum before the interaction is equal to the total momentum after the interaction.

The momentum of an object is calculated by multiplying its mass by its velocity. In this case, we have a cart with a mass of 100 kg moving at a velocity of 5 m/s, and a person running towards the cart with a velocity of 8 m/s.

Let's assume the mass of the person is m kg.

Before the interaction, the momentum of the cart is given by the product of its mass and velocity: 100 kg * 5 m/s = 500 kg·m/s.

The momentum of the person is given by the product of their mass and velocity: m kg * (-8 m/s) = -8m kg·m/s. The negative sign indicates that the person is moving in the opposite direction.

After the person jumps into the cart and the cart comes to a stop, the total momentum is zero. Therefore, we can set up the equation:

500 kg·m/s + (-8m kg·m/s) = 0

Simplifying the equation, we find:

500 kg·m/s - 8m kg·m/s = 0

492 kg·m/s = 8m kg·m/s

Dividing both sides of the equation by 8, we get:

m kg = 492 kg·m/s / 8 m/s

m kg = 61.5 kg

Therefore, the mass of the person is approximately 61.5 kg.