5 points The figure below shows two people ice-skating. Person A collides with
person B. After the collision they move together with the same velocity.
Calculate the mass, m, of person B.

Before collision
After collision
Person A
mass = 60 kg
Person B
mass, m
Person A and person B
moving off together
Speed of
Person A -
5.5 m/s
Speed of
Person B -
2.0 m/s
Speed of Person A and
Person B = 4.0 m/s

Imagine you are riding on a yacht in the ocean and traveling at 20 mph. you then hit a golf ball at 100 mph from the deck of the yacht. you see the ball move away from you at 100mph, while a person standing on a near by beach would observe your golf ball traveling at 120 mph (20 mph + 100 mph). now imagine you are aboard the hermes spacecraft traveling at 0.1c (1/10 the speed of light) past mars and shine a laser from the front of the ship. you would see the light traveling at c (the speed of light) away from your ship. according to einstein’s special relativity, how fast will a person on mars observe the light to be traveling? a) 0.1c (1/10 the speed of light) b) c (the speed of light) c)1.1c (c+0.1c)