Consider a freely spinning merry-go-round, which can be treated as a uniform disc of radius R and mass m1 rotating about a vertical axis through its center. Initially the merrygo-round is at rest. A boy of mass m2 jumps with a horizontal speed v, landing at A, which is a distance R 4 from the center. Hint: Neglect the vertical fall of the boy. m , v m R/4 O A R 1 2 As the boy is approaching the merry-goround, what is the magnitude of his initial angular momentum with respect to the center of the merry-go-round

Which is not a step in the rock cycle?

1. consider the case in which air fills air shocks on a truck trailer. the pressure in the shocks is 2 mpa. the temperature is 300 k. the diameter of the shock piston is 10 cm and the initial length of the cylindrical cavity containing the compressed air is 40 cm. a. the truck is gradually loaded over a period of a day in a static setting. the temperature is held constant for the atmosphere and thus for the gas shock. calculate the compressibility of the air in the shock for this condition when the truck is initially being loaded. b. if the shocks were loaded in a dynamic setting by driving over bumps, what would be the compressibility? state your assumption. c. what is the initial load on the shock if the shock is in an atmospheric 100 kpa? d. if the shock is compressed using the process described in part a, and the air shock compressed air cavity length decreases to 20 cm, what is the additional load applied to the shock?

Adding more pulleys to a system of pulleys needed to lift an object. a. increases the force b. decreases the force c. increases the amount of work d. decreases the amount of work