Measurements and Instrumentation

61

Which of the following transformers has low primary current?

A. Current transformer
B. Potential transformer
C. Distribution transformer
D. Both (a) and (b)

62

To measure an emf by dc potentiometer it is necessary to standardise the potentiometer with the help of a standard cell.

A. True
B. False

63

Assertion (A): A dc potentiometer measures the true open circuit emf of a source.

Reason (R): At balance point, a dc potentiometer does not draw any current from the source.

A. Both A and R are true and R is correct explanation of A
B. Both A and R are true but R is not correct explanation of A
C. A is true R is false
D. A is false R is true

64

Load cell uses

A. piezoelectric crystal
B. capacitor
C. mutual inductance
D. strain gauge

65

In a dynamometer instrument, the moving coil is pressure coil.

A. True
B. False