An engine does 18500 J of work and rejects 7810 J of heat into a cold reservoir whose temperature is 285 K. What would be the smallest possible temperature of the hot reservoir

Positrons are spontaneously emitted from the nuclei of

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.

Avector a⃗ has a length of 8.6 m and points in the negative x direction. find the x component of the vector −3.7a⃗ .