Q. Regarding the Earth and a cloud layer 750 m above the Earth as the "plates" of a capacitor, calculate the capacitance. Assume the cloud layer has an area of 1 km2 and that the air between the cloud and the ground is pure and dry.
Q. Two masses are suspended from a pulley as shown in the figure . The pulley itself has a mass of 0.30 , a radius of 0.20 , and a constant torque of 0.35 due to the friction between the rotating pulley and its axle.What is the magnitude of the acceleration of the suspended masses if = 0.40 and = 0.80 ? (Neglect the mass of the string.)