Entry Test MCQ :: Electromagnetic Induction

@ : Home > Physics > Electromagnetic Induction

11.

Self inductance of a coil depends upon

A.	current flowing	B.	number of turns per unit length
C.	voltage produce	D.	all

12.

If the coil is wound on an iron core the flux through it will

A.	decrease	B.	become zero
C.	remain the same	D.	increase

13.

Energy stored in a magnetic field is given by

A.	LI2	B.	L2I/2
C.	LI2/2	D.	IL2

14.

Inductors acts as a short circuit for

A.	AC	B.	DC
C.	Both (a) and (b)	D.	none of these

15.

For electroplating we use

A.	A D.C source	B.	an A.C source
C.	any source	D.	all of the above

16.

Which of the following uses electric energy and does not convert it into any other form?

A.	transformer	B.	motor
C.	D.C generator	D.	A.C generator

17.

The only difference between construction of D.C generator and A.C generator is that of

A.	carbon brushes	B.	coil
C.	commutator	D.	magnetic field

18.

A.C and D.C have the same

A.	effect in charging a capacitor	B.	effect in charging a battery
C.	effect while passing through an inductance	D.	heating effect through a resistance

19.

If the secondary coil has Ns turns and the primary Np turns the relation between secondary and primary voltages is given by

A.	Vs/Vp = Np/Ns	B.	Vs/Vp = Ns/Np
C.	Vp/Vs = Ns/Np	D.	Vp/Vs = Np/Ns

20.

Power loss in actual transformer is due to

A.	Small output	B.	Eddy currents and magnetic hysterias
C.	Soft iron core	D.	Back emf