# Electricity and Magnetism TNPSC Group 1 Questions

## Electricity and Magnetism MCQ Questions

1.
The unit of electrical conductivity is
A.
mho
B.
ohm
C.
D.
coulomb
A. mho
2.

Two resistances 18 Ω and 6 Ω are connected to a 6 V battery in series.

Calculate

(a) the total resistance of the circuit,

(b) the current through the circuit

A.

24 Ω and 0.25 A

B.

10 Ω and 0.20 A

C.

12 Ω and 1.30 A

D.

30 Ω and 0.25 A

A. 24 Ω and 0.25 A

3.
Three resistances having the values 5 Î©, 10 Î©, 30 Î© are connected parallel to each other. Calculate the equivalent resistance.
A.
B.
C.
D.
4.
One unit of electrical energy consumption is equal to
A.
1000 watt per hour
B.
500 watt per hour
C.
100 watt per hour
D.
None of these
A. 1000 watt per hour
5.

Consider the following statements:

Assertion (A) : In an electric bulb,the filament is in the form of a coiled coil

Reason (R ): A coiled coil filament occupies less space and id therefore,not cooled significantly by the convection current in the bulb.

A.

Both A and R are true, but R is the correct explanation of A

B.

Both A and R are true, but R is not the correct explanation of A

C.

A is true, but R is false

D.

A is false but R is true

A. Both A and R are true, but R is the correct explanation of A

6.

Consider the following statements:

Assertion (A) : Electric power is transmitted over long distances through conducting wires of very high voltages

Reason (R ): Then only the power can be supplied to the individual houses

A.

Both A and R are true, but R is not the correct explanation of A

B.

Both A and R are true and R is the correct explanation of A

C.

Both A and R are false

D.

A is false but R is true