1. The hot wire ammeter
- Is used only for dc circuits
- High precision instrument
- Used only for ac circuit
- Reads equally well on dc and ac circuit
2. The internal resistance of the milliammeter must be very low for
- High accuracy
- High sensitivity
- Minimum effect on the current in the circuit
- Maximum voltage drop across the meter
3. Assertion (A): shunt of an ammeter has low resistance.
Reason (R): shunt may be connected in series or in parallel with an ammeter.
- Both A and R are true and R is correct explanation of A
- Both A and R are true, but R is not correct explanation of A
- A is true, R is false
- A is false, R is true
4. Sensitive low voltage electronic components are protected from
- Static charge
- Induction circuit
- Lightening
- All of these
5. In order to convert to galvanometer into an ammeter
- A small resistance is connected in parallel to the coil of galvanometer
- A large resistance is connected in parallel to the coil of galvanometer
- A small resistance is connected in series to the coil of galvanometer
- A large resistance is connected in series to the coil of galvanometer
6. Which one of the following is used to measure direct current?
- Voltmeter
- Ammeter
- Pyrometer
- Coupler
7. A 10 mA ammeter has a resistance of 50 ohms. It is to be converted to a 1 A ammeter. The value of shunt resistance should be
- 5 ohms
- 0.1 ohms
- 0.505 ohms
- 0.05 ohms
8. Internal resistance of an ideal ammeter is
- Zero
- Infinite
- Small
- Big
9. Which instrument has the lowest resistance?
- Ammeter
- Voltmeter
- Megger
- Frequency meter
10. A DC ammeter has a resistance of 0.1 ohm and the current range is 0-100 A. If the range is to be extended to 0-500A, then meter requires shunt resistance of
- 0.010 ohm
- 0.011 ohm
- 0.025 ohm
- 1.0 ohm
11. In electrodynamometer ammeter, the deflection of the pointer is proportional to
- Mean of current in fixed coil and moving coil
- Square of the current in moving coil
- RMS value of current in fixed coil
- Mean-square of currents in fixed coil and moving coil
12. The multiplying power of the shunt of a milliammeter is 8. If the circuit current is 200 mA. Then current through the meter is
- 25 mA
- 200 mA
- 1600 mA
- 3200 mA
13. The measurement range of an ammeter can be increased by using a
- High resistance in shunt
- Low resistance in shunt
- High resistance in series
- Low resistance in series
14. An ammeter has a current range of 0-5 A, and its internal resistance is 0.2 ohm. In order to change the range to 0-25 A, what should be the value of resistance added and how it would connect with meter (i.e. series/parallel)?
- (0.05 ohm/series)
- (0.05 ohm/Parallel)
- (0.20 ohm/parallel)
- (0.20 ohm/series)
15. Clamp on ammeter is used for measurement of
- Large alternating currents
- Small direct currents
- Small alternating currents
- Large direct currents
16. Range of ammeter can extend by connecting
- A shunt parallel to ammeter
- A shunt in series to ammeter
- A multiplier parallel to ammeter
- A multiplier in series to ammeter
17. An instrument which detects electric current is known as
- Voltmeter
- Rheostat
- Wattmeter
- Galvanometer
18. A dc circuit can be represented by an internal voltage source of 50 V with an output resistance of 100 kΩ. In order to achieve 99 % accuracy for voltage measurement across its terminals, the voltage measuring device should have
- A resistance of atleast 10MΩ
- A resistance of 100 kΩ
- A resistance of atleast 10 Ω
- None of these
19. A voltage using a 20 microammeter movement has a sensitivity of
- 20 micro-ohm/volt
- 1000 ohm/volt
- 20,000 ohm/volt
- 50,000 ohm/volt
20. Ammeters are always connected in
- Series
- Parallel
- Either
- None