Topic 5(ii) : Electromagnetic Induction

Changing current in a coil produces emf in the same coil. this phenomenon is known as

• Mutual induction

• Self induction

• induced emf

• induced current

Self induced emf is always proportional to the time rate of change of the current.

• True

• False

SI unit for self inductance, L is

• Tesla(T)

• Weber(Wb)

• Henry(H)

• Farad (F)

When a constant current of 5.0 A flows in a 400 turns solenoid of length, l and cross sectional area A, emf is induced in the coil.

• True

• False

Which of the following factors DOES NOT affect the self inductance of a coil?

• The length of the coil

• The current flows in the coil

• The number of turn of the coil

• The cross sectional area of the coil

An inductor opposes any change in:

• voltage

• current

• frequency

• reactance

Where is the energy being stored in an inductor carrying a steady current ?

• In the electric field of the coil

• In the circuit

• In the power supply

• In the magnetic field of the coil

The phenomenon due to which there is an induced current in one coil due to the current in a neighboring coil is?

• Mutual induction

• Steady current

• Electromagnetism

• Self induction

If you wrap more coils around an electromagnet, it will become...

• brighter
• stronger
• weaker
• invisible

When a conductor is moved to cut through the magnetic flux, an _______________ is produced.

• induced current

• electromotive force

• electromagnetic induction

• internal resistance