Mass and Weight Standards 1.3

Mass Mass is the amount of matter in an object The mass of an object does not change when it is moved from place to place. Mass is measured in grams or kilograms

Weight Weight is measure of gravitational force acting on an object. Weight changes when the gravitational force changes. Weight = mass x gravity Weight is measured in newtons or pounds

Falling Objects Objects (on Earth) accelerate downwards at a rate of 9.8 m/s2 (10 m/s2) Terminal velocity occurs when acceleration of the falling object is 0 This is due to air resistance balancing with weight

Determining Velocity The formula for determining the velocity of a falling object after a time of t seconds is: Vf = g * t Example: An object that has fallen for 6 seconds. Vf = (9.8 m/s2) * (6 s) = 58.8 m/s

Determining Distance The distance which a free-falling object has fallen from a position of rest is also dependent upon the time of fall. This distance can be determined by the following formula: D = 0.5 x g x t2 or g x t2 2

Going Up Objects thrown straight up have their velocity decrease at the same rate as falling downward 9.8 m/s2 At the highest point their velocity is zero.

(gravity has been rounded up to 10 m/s2)