4 20 N effort is used in the 20 cm long spanner to unscrew a nut, then
calculate momentum to unscrew the nut.

Spend time observing or thinking about events that involve matter and energy. which events can you explain? which events can’t you explain?

Astudent looks at ocean waves coming into the beach. an ocean wave with more energy will a) have a greater height. b) have a greater period. c) travel toward the beach faster. d) strike the beach with greater frequency.

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?