Which force prevents objects from floating? 

Which force causes a ball to stop rolling on the floor? 

Humans are pulled down to the centre of the Earth. 

Which two forces do sky divers have pushing on them? 

In your experiment about air resistance, what was the control variable? 

The smallest parachute fell the fastest because it has less mass. 

Select the correct definition of 'friction.' 

Select the correct definition of 'force.' 

Which of these scenarios would air resistance be helpful for?