Gravitational Acceleration and Free Fall (1)

Earth's gravitational force

All object around us are pulled towards the centre of of Earth by Earth's gravitational force

Effects of gravitational force

Gravitational force causes an object to always fall downwards

Gravitational acceleration

An object such as the apple that falls due to Earth's gravitational force will experience gravitational acceleration

Symbol of gravitational acceleration

g

Free fall (1)

An object is said to experience free fall if its fall due to the effects of gravitational force only

Free fall (2)

For example, a sheet of paper does not freely because its motion is affected by air resistance

Free fall (3)

Objects falling freely, fall with the same gravitational acceleration no matter what their mass and shape are

Free fall (4)

Free fall only occurs in a vacuum, that is in a space with no air

Free fall (5)

In a vacuum chamber, a chicken feather and a tennis ball that are released from the same height will reach the bottom of the chamber silmultaneously

Motion graphs of an object experiencing free falls