1. Sparking occurs when a load is switched off because the circuit has high ?

resistance

inductance

capacitance

impedance

Answer: inductance

Explanation:


2. Electric current passing through the circuit produces ?

magnetic effect

luminous effect

thermal effect

all above effects

Answer: all above effects

Explanation:


3. Insulating materials have the function of ?

preventing a short circuit between conducting wires

preventing an open circuit between the voltage source and the load

conducting very large currents

storing very high currents

Answer: preventing a short circuit between conducting wires

Explanation:


4. Resistance of carbon filament lamp ...... as the applied voltage increases ?

increases

decreases

remains same

none of the above

Answer: decreases

Explanation:


5. The number of electrons in the outermost orbit of carbon atom is ?

3

4

6

7

Answer: 4

Explanation:


6. A rheostat differs from potentiometer in the respect that it ?

has lower wattage rating

has higher wattage rating

has large number of turns

offers large number of tappings

Answer: has higher wattage rating

Explanation:


7. For testing appliances, the wattage of test lamp should be ?

very low

low

high

any value

Answer: high

Explanation:


8. The rating of a fuse wire is always expressed in ?

ampere-hours

ampere-volts

kWh

amperes

Answer: amperes

Explanation:


9. Which of the following statement is true ?

A galvanometer with low resistance in parallel is a voltmeter

A galvanometer with high resistance in parallel is a voltmeter

A galvanometer with low resistance in series is an ammeter

A galvanometer with high resistance in series is an ammeter

Answer: A galvanometer with low resistance in series is an ammeter

Explanation:


10. Two lamps 100 W and 40 W are connected in series across 230 V (alternating). Which of the following statement is correct ?

100 W lamp will glow brighter

40 W lamp will glow brighter

Both lamps will glow equally bright

40 W lamp will fuse

Answer: 40 W lamp will glow brighter

Explanation: