1:-A transformer is an electrical device used to .

A:-change the frequency of applied AC voltage
B:-transfer electrical energy from one circuit to another without any direct electrical connection
C:-convert applied DC into AC
D:-convert applied AC into DC

2:-A 3-phase transformer has .

A:-1 primary and 3 secondary windings
B:-3 primary and 1 secondary windings
C:-3 primary and 3 secondary windings
D:-3 primary and 6 secondary windings

3:-A transformer has 800 turns in its primary winding and 200 in its secondary what is the primary voltage, if the secondary voltage is 40 V? Assume transformer losses as negligible?

A:-8 V
B:-16 V
C:-40 V
D:-160 V

4:-Efficiency of a transformer is the ratio of .

A:-Output power to input power
B:-Input power to output power
C:-Input current to output current
D:-Output current to input current

5:-The basic unit of capacitance is .

A:-Ohm
C:-Henry
D:-Mho

6:-The relationship between charge (Q), voltage (V) and capacitance (C) of a capacitor is .

A:-C = Q/V
B:-C = QV
C:-`"C=Q^2 V"`
D:-C = V/Q

7:-Identify the instrument which is NOT used for measurement of capacitance .

A:-Digital capacitance meter
B:-AC bridge
C:-RLC meter
D:-Kelvin bridge

8:-The capacitive reactance Xc is given by .

A:-2`Pi`FC
B:-1/2`Pi`FC
C:-2`Pi`/FC
D:-FC/2`Pi`

9:-Current flowing through a capacitor is given by .

A:-`"V.X_c"`
B:-`"V^2/X_c"`
C:-`"V/X_c"`
D:-`"V^2.C"`