1.When is friction desirable? A.Writing on a paper B.putting extra effort when walking. C.Reducing the serviceable life of the machine. D.Exerting a lot of effort to move the block on a rough surface.
2.all of the following statements describe undesirable friction EXCEPT______. A.Friction opposes the motion. B.Friction wears out things like tires and shoes. C.Friction holds tha nails steady while we hammer it. D.Friction makes the engines of automobiles use more fuel.
3.______is used to reduce the friction between parts and gears in a machine. A.Fuel B.Grease C.Oil D.Water
pa help po need kona yung 4-5 nasa picture po tapos paki answer yung check or ekis
