P = ρ QHg is the water power equation. Where H = heead = meter g = gravity =m/s2 ρ =density = (kg/m3) P = power = watt = N-m/sec Q = water flow rate = m3/sec
As you can see from the below figure in load Z1 is connected with the only current coil. In Load Z2 both current from the current coil (CC) and voltage from voltage coil (PC) are present (Power = V × I). Hence the Wattmeter will read power consumed by Z2.
When variable loss becomes equal to the constant loss, efficiency is maximum. Losses = Pi + Pc Since copper loss is a variable loss therefore Losses = Pi + Pi = 2pi Thus at a maximum efficiency of this transformer total loss = 150 x 2 = 300 W
EXAMIANS