A 20 kg block slides across a horizontal surface. If the coefficient of kinetic friction between the block and the surface is 0.20, what is the force of kinetic friction that acts on the block? Be sure to draw a free-body diagram.

Suppose that two tanks, 1 and 2, each with a large opening at the top, contain different liquids. a small hole is made in the side of each tank at the same depth 1.57 m below the liquid surface, but the hole in tank 2 has 2.49 times the cross-sectional area of the hole in tank 1. (a) what is the ratio ρ1/ρ2 of the densities of the liquids if the mass flow rate is the same for the two holes? (b) what is the ratio rv1/rv2 of the volume flow rates from the two tanks? (c) at one instant, the liquid in tank 1 is 14.9 cm above the hole. if the tanks are to have equal volume flow rates, what height above the hole must the liquid in tank 2 be just then?

If the ama of the inclined plane below is 2, calculate the ima and efficiency. ima = efficiency =

Which situation will produce the greatest change of momentum