A typical heavy stratocumulus cloud layer has an optical thickness t* = 50, = 1, and g = 0.85 in the visible band. (a) Compute its albedo and total transmittance. (b) If the cloud were perfectly absorbing rather than perfectly scattering, what optical thickness would yield the same transmittance as in (a), assuming Ji = 0.5

As you are trying to move a heavy box of mass m, you realize that it is too heavy for you to lift by yourself. there is no one around to , so you attach an ideal pulley to the box and a massless rope to the ceiling, which you wrap around the pulley. you pull up on the rope to lift the box. use g for the magnitude of the acceleration due to gravity and neglect friction forces. once you have pulled hard enough to start the box moving upward, what is the magnitude f of the upward force you must apply to the rope to start raising the box with constant velocity? express the magnitude of the force in terms of m, the mass of the box.

Two forces produce equal torques on a door about the door hinge. the first force is applied at the midpoint of the door; the second force is applied at the doorknob. both forces are applied perpendicular to the door. which force has a greater magnitude?

Compare the horizontal displacement of the two balls as they travel to the ground. what do you observe?