A 0.2 kg ball moves to the right with a speed of 3 m/s. It hits a 0.5 kg ball that at rest. After collision, the second ball moves to the right with a speed of 1 m/s. What is the speed of the first ball after collision?

To find the speed of the first ball after the collision, 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 its velocity. Let's denote the velocity of the first ball after the collision as v1' and the velocity of the second ball after the collision as v2'.

Before the collision:
Momentum of the first ball = mass of the first ball * velocity of the first ball
Momentum of the second ball = mass of the second ball * velocity of the second ball (since it is at rest, its velocity is 0)

After the collision:
Momentum of the first ball = mass of the first ball * velocity of the first ball after the collision (v1')
Momentum of the second ball = mass of the second ball * velocity of the second ball after the collision (v2')

Using the conservation of momentum, we can write:

(mass of the first ball * velocity of the first ball) + (mass of the second ball * velocity of the second ball) = (mass of the first ball * velocity of the first ball after the collision) + (mass of the second ball * velocity of the second ball after the collision)

Now let's substitute the given values into the equation:

(0.2 kg * 3 m/s) + (0.5 kg * 0 m/s) = (0.2 kg * v1') + (0.5 kg * 1 m/s)

Simplifying the equation:

0.6 kg m/s = 0.2 kg v1' + 0.5 kg

0.2 kg v1' = 0.6 kg m/s - 0.5 kg

0.2 kg v1' = 0.1 kg m/s

v1' = 0.1 kg m/s / 0.2 kg

v1' = 0.5 m/s

Therefore, the speed of the first ball after the collision is 0.5 m/s.

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You seem to want answers, not help.