Elephants can communicate using very low frequency sound waves over long distances. An elephant makes a noise below human hearing at 16Hz. This low rumble moves at 350 m/s (speed of sound in air). This sound is detected by her friend 25 seconds later.
How far away is her friend?

Nitrogen (n2) undergoes an internally reversible process from 6 bar, 247°c during which pν1.2 = constant. the initial volume is 0.1 m3 and the work for the process is 121.14 kj. assuming ideal gas behavior, and neglecting kinetic and potential energy effects, determine heat transfer, in kj, and the entropy change, in kj/s. show the process on a t-s diagram.