1) 1. Which of the following situations show that friction is helpful? a) brakes used on a bike b) tires from a car on the road c) tread on the bottom of your shoes d) all of the above 2) Which is NOT a way of reducing friction? a) making rough surfaces b) making the surfaces smoother c) using lubricants such as waxes, oils, or grease d) changing from sliding friction to rolling friction using ball bearings 3) Which can cause the greatest friction? a) polished floor b) rough floor c) tiled floor d) wet floor 4) Which type of friction is used when an object moves through a liquid or gas? a) dry b) fluid c) sliding d) static 5) How can friction be reduced? a) use wax, grease or oil b) reduce the force acting between the 2 surfaces c) reduce the roughness of the 2 surfaces coming in contact d) D. All of the above are ways of reducing friction

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