An aircraft engine takes in 8950 j of heat and discards 6150 j each cycle. part a)
what is the mechanical work output of the engine during one cycle?
part b)
what is the thermal efficiency of the engine?

Aballet student who learns with the of his instructor is demonstrating learning.

Because air contracts as it cools, the air pressure inside a freezer is typically lower than on the outside. why do ice cubes inside a freezer tend to shrink over time? a. the ice dissolves oxygen from the air, forming a denser crystalline matrix. b. the ice reacts chemically with carbon dioxide in the air, forming gaseous carbon compounds. c. the ice melts, and then the liquid freezes as ice crystals on the bottom of the freezer. d. the ice sublimes, and then the water vapor deposits as ice crystals on the sides of the freezer.

Which accurately compares concave and convex lenses?