An ac bridge uses galvanometer as detector.

For critical damping, the resistance in D'Arsonval galvanometer circuit should be equal to

Two resistances are R₁ = 36 ± 5% and R₂ = 75 ± 5%. If they are connected in parallel, the limiting error in percent will be

The sensitivity of a potentiometer can be increased by

An average responding voltmeter using full wave rectifier has been calibrated to read 1 V for 1 V rms sinusoidal input. For 1 V peak to peak square wave input, the meter reading will be