Question

Мяч массой 0,4 кг после удара о стену продолжает двигаться с прежней по значению скоростью а направление скорости после удара составляет угол 90 градусов с направление скорости до удара.Модуль изменения импульса мяча при ударе равен 5,6 кг*км/с.Определите скорость мяча.

Answer 1

Изменение импульса (по направлению):
Δp=m*ΔV =m√(V²+V²)=√2*m*V
Скорость:
V=Δp / (√2*m) = 5,6 / (√2*0,4) = 14/√2 ≈ 10 м/с

Answer 2

Problem Analysis

We are given the following information: - A ball with a mass of 0.4 kg continues to move with the same speed after hitting a wall. - The direction of the ball's velocity after the collision forms a 90-degree angle with the direction of the velocity before the collision. - The change in momentum of the ball during the collision is 5.6 kg*m/s.

We need to determine the velocity of the ball.

Solution

To solve this problem, we can use the principle of conservation of momentum. According to this principle, the total momentum before the collision is equal to the total momentum after the collision.

The momentum of an object is given by the product of its mass and velocity. Therefore, we can write the equation for the conservation of momentum as:

Initial momentum = Final momentum

The initial momentum of the ball before the collision is given by the product of its mass and velocity:

Initial momentum = mass * initial velocity

The final momentum of the ball after the collision is given by the product of its mass and final velocity:

Final momentum = mass * final velocity

Since the ball continues to move with the same speed after hitting the wall, the magnitude of the initial velocity is equal to the magnitude of the final velocity. However, the direction of the velocity changes by 90 degrees.

Let's assume the magnitude of the velocity is v. The initial velocity can be represented as v in one direction, and the final velocity can be represented as v in a direction perpendicular to the initial velocity.

Using the conservation of momentum equation, we can write:

mass * initial velocity = mass * final velocity

Substituting the values given in the problem, we have:

**0.4 kg * v = 5.