Question

A boy sleds down a hill and onto a frictionless ice-covered lake at 10.0 m/s. In the middle of

the lake is a 1000-kg boulder. When the sled crashes into the boulder, he is propelled backwards

from the boulder. The collision is an elastic collision. If the boy’s mass is 40.0 kg and the sled’s

mass is 2.50 kg, what is the speed of the sled and the boulder after the collision? Show all work and sketches

Answer 1