Page 872 - Basic Electrical Engineering

c. square of the maximum value of current
d. maximum value of the current.

17. We can distinguish between a moving-iron-type and a moving-coil-type instrument by
working at their

a. pointer
b. graduated scale
c. size
d. all the items as in (a), (b), and (c).

18. In a moving iron instrument 8 A current causes a deflection of the needle over the scale by
60º. For a deflection of 15º, the current required will be

a. 2 A
b. 4 A
c. 16 A
d. 0.5 .
A
19. A voltmeter must have very high internal resistance so that

a. its accuracy is high
b. its resolution is high
c. it draws a very small amount of current
d. it creates a high loading effect on the circuit.

20. An instrument with a measurement range of 0–100 V with an accuracy of percentage has been
used to measure a low voltage of 10 V. The error of measurement will be

a. 1 per cent
b. 0.1 per cent
c. 0.01 per cent
d. 10 per cent.

Answers to Multiple Choice Questions

1. (c) 2. (b) 3. (a) 4. (c) 5. (b)
6. (a) 7. (a) 8. (c) 9. (b) 10. (a)

11. (b) 12. (b) 13. (c) 14. (b) 15. (a)

16. (a) 17. (b) 18. (b) 19. (c) 20. (d)