You and your friends are doing physics experiments on a frozen pond that serves as a frictionless, horizontal surface. Sam, with mass 80.0 kg, is given a push and slides eastward. Abigail, with mass 50.0 kg, is sent sliding northward. They collide, and after the collision Sam is moving at 37.0o north of east with a speed of 6.00 m/s and Abigail is moving at 23.0o south of east with a speed of 9.00 m/s. (a) What was the speed of each per-son before the collision? (b) By how much did the total kinetic energy of the two people decrease during the collision?

Solution 74P Problem (a) Step 1: Mass of Sam m = 80.01 Mass of Abigail m = 50.0Kg 2 Final velocity of Sam v = 6.001/s (north of east) = 37.0° Final velocity of Abigail v = 9.00 m/s (south of east) 2 = 23.0°