# Science - Force & Work

 What is force? This is a push or pull that can change the speed, the direction or the shape of the body List examples of force Push Pull Weight Friction State the unit used to measure force Newton (N) What is gravity? Gravity is the force that pulls things towards the earth What is weight? The weight of an object is the force of gravity acting on it State the unit used to measure weight Newton (N) What instrument is used to measure weight? Spring balance Explain what is meant by the term friction Friction is the force that slows down moving things Give examples of friction Tyres use friction to grip the road Brakes use friction to slow down cars State a way to reduce friction Oil Grease Give an advantage of friction Friction slows things down eg. brakes on a car use friction to slow the wheels down State a disadvantage of friction Friction between surfaces can wear them away eg. it can wear brake pads down Explain Hooke's Law This states that the extension of a spring is directly proportional to the force that is stretching it What is work? Work is when a force makes something moves State the unit used to measure work Joule (J) What is power? Power is how fast work is done State the unit used to measure power Watt (W) Authormshowley ID150768 Card SetScience - Force & Work DescriptionForce & Work Updated2012-04-28T22:48:01Z Show Answers