Question

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

a.

2.0 μH/rad

b.

4.8 μH/rad

c.

12.0 μH/rad

d.

114.6 μH/rad

Answer: (b).4.8 μH/rad

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Q. A moving iron ammeter produces a full-scale torque of 240 μN-m with a deflection of 120° at a current of 10 A. the rate of change of self-inductance (μH/rad) of the instrument at...

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