two positive point charges are a fixed distance apart. the sum of their charges is Qt. what charge must each have in order to (a) to maximise the electric force between them (b) minimise it?

Agas contained within a piston-cylinder assembly undergoes three processes in series: process 12: compression with pv= constant from 1 bar and 1 liter to 4 bar. process 23: constant pressure expansion to 1 liter. process 31: constant volume calculate the pressure and volume at each state, and sketch the processes on a p-vdiagram labeled with pressure and volume values at each numbered stat