Question

When the moving coil in a Dynamometer type wattmeter deflects ________

(a) pointer moves

(b) pointer doesn’t move

(c) current flows

(d) voltage is generated

I had been asked this question in a national level competition.

Query is from Dynamometer Type Wattmeter topic in division Measurement of Power and Related Parameters of Electrical Measurements

Answer 1

Right answer is (a) pointer moves

For explanation: In a Dynamometer type wattmeter, when the moving coil deflects the pointer moves over the scale. The pointer then comes back to rest at a point where the deflecting torque equals the controlling torque.