Suppose an electric charge p(x, y) is uniformly spread on a disc of radius r around the origin. use maxwell's first equation (in a non-dimensional version) (4) v e = p from the origin r > r, the field is proportional to r-1. that far to prove away do not use the explicit formula for the electric field. do use the fact that the electric field points towards the charged particle, and whatever symmetries this problem has.

An inclined plane wrapped around a metal shaft is a a. lever b. screw c. pulley d. wedge

The astronauts on the space shuttle flights experienced an acceleration of 29 m/s2 (about 3 "g's") during lift-off. what upward force must the astronaut's seat apply to the astronaut in order to cause this acceleration? assume the astronaut's mass is 70 kg, and compute this force when the acceleration is near the earth's surface so their weight equals latex: mg m g .

Acommercial refrigerator with refrigerant-134a as the working fluid is used to keep the refrigerated space at -35°c by rejecting waste heat to cooling water that enters the condenser at 18°c at a rate of 0.25 kg/s and leaves at 26°c. the refrigerant enters the condenser at 1.2 mpa and 50°c. if the compressor consumes 3.3 kw of power, determine (a) the mass flow rate of the refrigerant, (b) the refrigeration load, (c) the cop, and (d) the minimum power input to the compressor for the same refrigeration load.