A dc voltage with ripple is given by . Measurements of this voltage v(t), made by moving-coil and moving-iron voltmeters, show reading of  and  respectively. The value of in volts, is_____________.

The saw-tooth voltage waveform shown in the figure is fed to a moving iron voltmeter. Its reading would be close to_____________.

A periodic waveform observed across a load is represented by

The measured value, using moving iron voltmeter connected across the load, is

Three moving iron type voltmeters are connected as shown below. Voltmeter readings are V,  and , as indicated. The correct relation among the voltmeter readings is  

A moving iron ammeter produces a full-scale torque of 240 µNm with a deflection of 120° at a current of 10 A. The rate of change of self inductance (µH/radian) of the instrument at full scale is?

The inductance of a certain moving-iron ammeter is expressed as , where θ is the deflection in radians from the zero position. The control spring torque in  Nm/radian, the deflection of the pointer in radian when the meter carries a current of 5A, is

An unshielded moving iron voltmeter is used to measure the voltage in an a.c. circuit. If a stray d.c. magnetic field having a component along the axis of the meter coil, the meter reading would be