Question

Очень нужно......40 баллов куля масою 3 кг летить зі швидкістю 6м.с і стискається з нерухомою кулею масою 4 кг.Якими будуть напрям та значення швидкості першої кулі після абсолютного пружного удару , якщо друга габула швидкості 2.мс?

Answer 1

По закону сохранения импульса
m1V1=m1U1+m2U2 ---->U1=(m1V1-m2U2)/m1
U1=(3*6-4*2)/3=3,3 м/c

Answer 2

Problem Analysis

We are given two spheres colliding with each other. The first sphere has a mass of 3 kg and is moving with a velocity of 6 m/s. The second sphere has a mass of 4 kg and is initially at rest. We need to determine the direction and magnitude of the velocity of the first sphere after the collision, assuming it is an elastic collision. The velocity of the second sphere after the collision is given as 2 m/s.

Solution

In an elastic collision, both momentum and kinetic energy are conserved. Let's denote the initial velocity of the first sphere as v1i, the final velocity of the first sphere as v1f, the initial velocity of the second sphere as v2i, and the final velocity of the second sphere as v2f.

According to the law of conservation of momentum, the total momentum before the collision is equal to the total momentum after the collision:

m1 * v1i + m2 * v2i = m1 * v1f + m2 * v2f

where m1 and m2 are the masses of the first and second spheres, respectively.

Substituting the given values, we have:

3 kg * 6 m/s + 4 kg * 0 m/s = 3 kg * v1f + 4 kg * 2 m/s

Simplifying the equation, we get:

18 kg m/s = 3 kg * v1f + 8 kg m/s

Rearranging the equation, we find:

3 kg * v1f = 18 kg m/s - 8 kg m/s

3 kg * v1f = 10 kg m/s

Dividing both sides of the equation by 3 kg, we get:

v1f = 10 kg m/s / 3 kg

v1f ≈ 3.33 m/s

Therefore, the magnitude of the velocity of the first sphere after the collision is approximately 3.33 m/s.

Since the second sphere is initially at rest, its final velocity after the collision is equal to the negative of the final velocity of the first sphere:

v2f = -v1f

Substituting the value of v1f, we have:

v2f ≈ -3.33 m/s

Therefore, the magnitude of the velocity of the second sphere after the collision is approximately -3.33 m/s.

Since the second sphere is moving in the opposite direction to the first sphere, the direction of its velocity is opposite to that of the first sphere.

To summarize: - The magnitude of the velocity of the first sphere after the collision is approximately 3.33 m/s. - The magnitude of the velocity of the second sphere after the collision is approximately -3.33 m/s. - The direction of the velocity of the second sphere is opposite to that of the first sphere.

Please note that the negative sign indicates the opposite direction.