A solar-powered water pump raises a volume VVV of water, of density ρ\rhoρ, from a well of depth ddd in a time interval ttt. During this time, the solar panels supply a constant electrical power PPP to the pump. If the acceleration due to gravity is ggg, which of the following expressions represents the efficiency of the pump system?
ρVgdPt\frac{\rho V g d}{P t}PtρVgd
PtρVgd\frac{P t}{\rho V g d}ρVgdPt
ρVgPdt\frac{\rho V g P}{d t}dtρVgP
ρVgdtP\frac{\rho V g d t}{P}PρVgdt
84 exam-style questions on AQA A Level Physics Force, energy and momentum, covering Scalars and vectors, Moments, Motion along a straight line, Projectile motion, Newton's laws of motion, Momentum, Work, energy and power, and Conservation of energy. Each one has a worked solution and a mark scheme showing where the marks go.