# 12th Physics Unit 15 Chapter Wise Past Papers MCQs 12th Physics unit 15 electromagnetic induction MCQs. All MCQs are from previous Boards papers of Inter part 2. 2nd year Physics chapter wise past papers fully solved MCQs.

## 12th Physics Unit 15 MCQs:

### 2nd Year Physics Past Papers MCQs:

Split rings are used in:
(A) A.C generator
(B) A.C motor
(C) Transformer
(D) D.C motor

The jerks in D.C motor are created by the use of: (DGK. GII, 2017)
(A) Armature
(B) Commutators
(C) Slip rings
(D) Source of emf

Output of D.C motor is: (GRW. GII, 2017)
(A) A.C energy
(B) Mechanical energy
(C) Chemical energy
(D) D.C energy

The self induction emf is sometimes called: (BWP. GI. 2017)
(A) Motional emf
(B) Constant emf
(C) Back emf
(D) Variable emf

When a motor is over loaded then the magnitude of back emf: (DGK. BWP. GI, 2018)
(A) Increases
(B) Decreases
(C) Remains constant
(D) Zero

When the back emf is zero, its draws: (AJK. GI, 2014) (MLN. GI, 2017)
(A) Zero current
(B) Minimum current
Maximum current

#### Fsc part 2 Physics Electromagnetic Induction MCQs:

The Self induction is given by: (GRW. GI, 2014) (GRW. GII, 2015)
(A) NL = 01
(B) NI = 0L
(C) No = LI
(D) N=LI

The inductance can be increased by winding the wire around a core made of: (LHR. GII, 2014)
(A) Copper
(B) Silicon
(C) Iron
(D) Alumium

With the increase in speed of motor the magnitude of back emf: (SGD. GII, FBD. GI, 2017)
(A) remain same
(B) Increases
(C) decreases
(D) first increases then decreases

When motor is just started, back emf is almost: (MLN. GII, 2016) (LHR. GII, 2018)
(A) Maximum
(B) Zero
(C) Minimum
(D) Infinite

The term has the same dimensions as: (LHR. GII, 2016)
(A) Flux
(B) Potential difference
(C) Time
(D) Current

By winding the cold around a fess magnetic core, self-induction: (GRW.GI, 2016)
(A) Will increase
(B) Will decrease
(C) Remain same
(D) First increase then decrease

If D.C is input for a step-up transformer, then output is: (GRW. GI, 2017)
(A) Zero
(B) High
(C) Low
(D) Maybe high or low

#### Unit 15 12th Class

The working principle of transformer is: (LHR. GII, 2015)
(A) Self induction.
C) Mutual induction
(D)Electromagnetic induction

Unit of self inductance is: (SGD. GI, 2016) (LHR. GII, 2018)
(A) Weber
(B) Tesla
(C) Henry

Henry is SI unit of: (GRW. GI, 2016)
(A) Current
(B) Resistance
(C) Flux
(D) Self induction

The application of mutual induction is a: (MLN. GI, 2014)
(A) D.C motor
(C) Television
(D) Transformer

Self induction does not depend on: (RWP. GI, 2016)
(A) Number of turns of the coil
(B) Area of cross-section of the core
(C) Nature of material of the core
(D) Energy stored in an inductor

For step down transformer. (RWP. GI, 2014) (SWL. GI, 2017)
(A) Ns > Np
(B) Np > Ns
(C) Ns = Np
(D) Ns >>> Np