unit19

Unit 19 is about gravitational force and frictional force . In unit 19 we made a parachute and we read many pages of explanation text and do self check.Frictional force can cause problem on car engine to overheat and causes a car to stop.I learned how tread patterns on shoes and car tires could save a person's life ,how fingerprints could help grip something , gravitational force could pull divers downwards,could speed up a skier in the hill skiing ,could pull things down that is all for sumarising unit 19