How are electromagnetic waves produced? a) an accelerating electric point charge (electron) emits electromagnetic waves. b) a bar magnet moving in a strong electric field produces electromagnetic waves. c) a large electromagnet operated at very high voltages produces electromagnetic waves. d) a stable nucleus moving through a stable magnetic field produces electromagnetic waves.

Avertical clean glass piezometer tube has an inside diameter of d = 1 mm and is used to measure pressure in a horizontal pipe carrying water as shown. due to pressure in the pipe, the water at 20c rises into the tube to a height h. if the water pressure in the pipe is p = 500 pa gauge, estimate the height h: (a) without considering surface tension (b) with surface tension (capillary) effects. the contact angle  can be assumed at 30 deg