Mass vs. Weight Homework: Read 4.6-4.9 and be prepared for a brief quiz Tomorrow Relationship between Mass and Weight Mass and weight are related, but they are not the same. Fw = mg Ex. : Fw = (2 kg)(-10 m/s2) = -20 N In words: The force of weight equals mass times the acceleration due to gravity Mass vs. Weight You will be able to differentiate between mass and weight… Apparent weight – force exerted by a scale Weightlessness – an apparent weight of zero W = Fg = mg Weight mass 1 kg = 10 N Example Problem: Your mass is 75 kg. You stand on a scale in an elevator that is going up at 2.0 m/s2. A) What is your weight (before entering the elevator)? B) What is your apparent weight (on the elevator? C) Is this larger, smaller, or equal to your weight at rest?