Question

a boy is at rest on a sheet of flat frictionless ice. he throws a snowball of mass 0.02 kg at a speed of 18 m/s in a horizontal direction. if his mass is 75 kg, how fast will the recoil make him drift on the ice?

Answer 1

The recoil from throwing the snowball will make the boy drift on the ice with a speed of 0.02 m/s in the opposite direction of the throw.

Step-by-step explanation:

To find the speed at which the boy drifts on the ice after throwing the snowball, we can use the principle of conservation of momentum. The initial momentum is zero since the boy is at rest, and the final momentum is the product of his mass and velocity. Since there is no external force, the total momentum before and after throwing the snowball must be equal.

Before throwing the snowball:

• The boy's mass = 75 kg
• The snowball's mass = 0.02 kg
• The snowball's velocity = 18 m/s

After throwing the snowball:

• The boy's velocity = ???
• The snowball's velocity = 0 m/s (it comes to rest)

Using the equation:

initial momentum = final momentum

0 = (75 kg) * v + (0.02 kg) * 0 m/s

solving for v, the boy's velocity, we get:

v = -0.02 m/s

Therefore, the recoil from throwing the snowball will make the boy drift on the ice with a speed of 0.02 m/s in the opposite direction of the throw.