Without friction, a bicycle wouldn't work, this is because there would be no grip on the road surface or pedals and no way to stop the wheels from going around. Ice-skating also demonstrates friction, with the edge of the blades as the centre of gravity. Air resistance or drag, acts against gravity on falling objects and this is how parachutes work. Swimmers also use water resistance to help them move forward.

This clip is from:
Primary Focus Science
First broadcast:
15 April 2008

The clip could be used to stimulate investigations into parachutes. Children could look at how different variables affect the rate a parachute falls, from the material the parachute is made from, to the surface area of the parachute. This could be done as a fair test with the children making the parachutes and timing how long they take to fall to the ground, investigating just one variable at a time. Equally an investigation into paper helicopters could be carried out in the same way, with variables of propeller width and the number of propellers being looked at. Links with nature and seed dispersal could also be investigated, and how plants design their seeds so that they can travel as far as possible away from the parent plant.