Two persons a and b do same amount of work. the person a does that work in t1sec and the person b in t2sec. find the ratio of power delivered by them.

Clothes dryer uses about 7 amps of current from a 240 volt line. how much power does it use?

Which component of the earth’s atmosphere is decreased due to photosynthesis?

Engines for propeller-driven aircraft are limited in their maximum rotational speed by the fact that the tip speed of the propeller must not approach the speed of sound in air (mach i). taking 6 ft as a typical diameter for a propeller of a light airplane and 1100 fils as the speed of sound, find the upper limit on the rpm (revolutions per minute) of the propeller shaft.