1. In moving iron instruments, the damping torque is provided by
(A) fluid friction damping.
(B) air friction damping.
(C) eddy current damping.
(D) none of these.
Answer ⇓
2. The pointer of an indicating instrument is generally made of
(A) copper.
(B) aluminium.
(C) brass.
(D) soft steel.
Answer ⇓
3. What will happen if the ammeter is connected like a voltmeter in parallel to the load?
(A) there will no current in the circuit.
(B) ammeter will work as voltmeter.
(C) very high current will flow.
(D) nothing will happen in the circuit.
Answer ⇓
4. Shunts are generally made of
(A) nichrome.
(B) manganin.
(C) copper.
(D) carbon.
Answer ⇓
5. Which of the following is used to measure the inductance
(A) Wien Bridge.
(B) Schering Bridge.
(C) Maxwell Bridge.
(D) Owen Bridge.
Answer ⇓
6. A moving coil galvanometer is made into a DC ammeter by connecting
(A) high resistance in series with meter.
(B) low resistance in parallel with meter.
(C) an inductance in parallel with meter.
(D) inductance in series with meter.
Answer ⇓
7. If any instrument obey Square Law, it can be used for the measurement of
(A) AC only.
(B) pure DC only.
(C) both AC and DC.
(D) pulsating DC only.
Answer ⇓
8. Hysteresis error, in moving iron instruments, may be reduced by using
(A) silicon Steel.
(B) stainless steel.
(C) permalloy or mumetal.
(D) silver coating.
Answer ⇓
9. Resolution of an instrument is
(A) the minimum quantity it can measure.
(B) the maximum quantity it can measure.
(C) the maximum non linearity.
(D) the maximum accuracy.
Answer ⇓
10. The ratio of torque to the weight of an instrument is known as
(A) accuracy.
(B) reliability.
(C) sensitivity.
(D) selectivity.
Answer ⇓
11. A CRO uses
(A) electromagnetic focusing.
(B) magnetic focusing.
(C) electrostatic focusing.
(D) dynamic focusing.
Answer ⇓
12. The resistance of an ideal voltmeter is
(A) zero.
(B) infinite.
(C) very low.
(D) equal to load resistance.
Answer ⇓
13. The resistance of an ideal ammeter is
(A) zero.
(B) infinite.
(C) very high.
(D) equal to load resistance.
Answer ⇓
14. If permanent magnet moving coil instruments is connected to AC supply, the average torque produce will be
(A) very high.
(B) normal.
(C) low.
(D) zero.
Answer ⇓
15. A moving iron instrument can be used for measuring
(A) D.C. only.
(B) A.C. only.
(C) both D.C. and A.C.
(D) none of the above.