Electricity & Magnetism MCQs with Answers

When the back e.m.f in a circuit is zero, it draws?

• A.Constant current
• B.Minimum current
• C.Zero current
• D.Maximum current

Past Paper MCQ

In which is more electricity conducted?

• A.Steel
• B.Rubber
• C.Glass
• D.Plastic

A semi-conductor has ?

• A.Negative conductivity
• B.High conductivity
• C.No conductivity
• D.Small conductivity

If R1 and R2 are respectively the filament resistance of a 100-Watt bulb and 200-Watt bulb designed to operate on the same voltage, then:

• A.R1 is two times R2
• B.R2 is two times R1
• C.R1 is four times R2
• D.R1 and R2 are equal

In the relation between voltage (V) and current (I), the proportional constant is:

• A.W
• B.P
• C.Q
• D.R

The time rate of change of magnetic flux has the same dimension as that of _?

• A.Potential difference
• B.Electric current
• C.Resistance
• D.Capacitance

Drift velocity of an electron is ?

• A.10^3 m/sec
• B.10^-6 m/sec
• C.3 × 10^8 m/sec
• D.10^-3 m/sec

Which of the following is a conductor of electricity?

• A.Water
• B.Glass
• C.Rubber
• D.Plastic

If the number of turns in a coil is doubled and length remains the same, then the magnetic flux linked with it ?

• A.Becomes four times
• B.Is halved
• C.Remains unchanged
• D.Is doubled

_ is a phenomenon of exactly zero electrical resistance and expulsion of magnetic fields occurring in certain materials when cooled below a characteristic critical temperature.

• A.Superfluidity
• B.Superconductivity
• C.Ferromagnetism
• D.Dielectric breakdown