A 50 kg ice hockey player standing on a frictionless ice surface throws a ball, mass of 5.0 kg horizontally with a speed of 3.0 m/s. With what speed will the player recoil?

• What formula/s should I use?

To solve this problem, you can use the law of conservation of momentum. According to this law, the total momentum before the throw is equal to the total momentum after the throw. Momentum is the product of an object's mass and its velocity.

The formula for momentum is:

Momentum (p) = mass (m) x velocity (v)

Using this formula, you can calculate the momentum of the ball before the throw and the momentum of the player after the throw. Since the ice surface is frictionless, there are no external forces acting on the system, so the total momentum remains constant.

The formula to calculate total momentum before and after the throw is:

Total momentumbefore = Total momentumafter

(mass of player before x velocity of player before) + (mass of ball before x velocity of ball before) = (mass of player after x velocity of player after) + (mass of ball after x velocity of ball after)

Now, let's calculate the velocities.

The player is initially at rest, so the velocity of the player before the throw is 0 m/s.

Plugging in the given values:

(50 kg x 0 m/s) + (5 kg x 3.0 m/s) = (50 kg x velocity of player after) + (5 kg x velocity of ball after)

Now, we need to solve this equation to find the velocity of the player after the throw. Let's rearrange the equation:

(5 kg x 3.0 m/s) = (50 kg x velocity of player after) + (5 kg x velocity of ball after) - (50 kg x 0 m/s)

15 kg·m/s = 50 kg x velocity of player after + 5 kg x velocity of ball after

To find the velocity of the player after the throw, we can isolate it by rearranging the equation:

50 kg x velocity of player after = 15 kg·m/s - (5 kg x velocity of ball after)

velocity of player after = (15 kg·m/s - (5 kg x velocity of ball after)) / 50 kg

So, to find the velocity of the player after the throw, you need to substitute the velocity of the ball after it has been thrown into this equation.