Magnetic Effects of Electric Current

In this article, we are sharing Physics MCQ – Magnetic Effects of Electric Current.

Magnetic Effects of Electric Current

Q. H.C. Oersted established the relation between magnetism and ………..(in 1820).

(A) potential
(B) potential difference
(C) electricity
(D) charge

Q. MRI stands for:

(A) magnetic resonance interference
(B) magnetic resonance imaging
(C) magnetic re-scanning imaging
(D) none of these

Q. Magnitude of magnetic field product around a conductor depends upon:

(A) voltage
(B) current
(C) thickness
(D) length of conductor

Q. How many magnetic poles are there in a current carrying solenoid?

(A) two
(B) four
(C) one
(D) six

Q. ……..and……..are the two alloys used to make permanent magnets:

(A) Alnico, duralumin
(B) nipermag, titanium
(C) Nipermag, alnico
(D) titanium, duralumin

Q. When we move away from a magnetized wire magnitude of magnetic field………..

(A) Increases
(B) Decreases
(C) Remains same
(D) is doubled

Q. What is the unit magnitude of the magnetic field?

(A) faraday
(B) Tesla
(C) newton
(D) newton/m

Q. Current that does not change its direction after equal intervals of time is called:

(A) direct current
(B) indirect current
(C) Alternating current
(D) Static electricity

Q. In Fleming’s left-hand rule middle finger represents the  of:

(A) magnetic field
(B) motion of conductor
(C) induced current
(D) flowing current

Q. Fleming’s right rule is used in:

(A) A.C generator
(B) Electric motor
(C) D.C generator
(D) (a) and (c)

Q. In right-hand rule thumb represents the direction of:

(A) the motion of conductor
(B) magnetic field
(C) induced current
(D) flowing current

Q. In A.C generator and D.C generator main difference is in:

(A) coils
(B) speeds
(C) rings
(D) magnets

Q. On increasing number of turns magnetic field of a solenoid:

(A) Decrease
(B) Increase
(C) no effects
(D) none of these

Q. Which magnet is used to lift heavy goods?

(A) U-shape magnet
(B) bar magnet
(C) Electromagnet
(D) simple magnet

Q. What is the effect of heating on a magnet?

(A) magnetism will increase
(B) magnetism will decrease
(C) no effect
(D) none of these

Q. Which magnet is more powerful?

(A) U-shape magnet
(B) bar magnet
(C) Electromagnet
(D) simple magnet

Q. Magnetic compass acts on the principle of:

(A) magnetism
(B) electromagnet
(C) electric fuse
(D) none of these

Q. Electric supply in homes and factories is:

(A) 220V and 400V
(B) 400V and 220V
(C) 220V and 440V
(D) 440V and 220V

Q. Which shock is more dangerous?

(A) A.C
(B) D.C
(C) both (a) and (b)
(D) none of these

Q. Two circuits used in homes are of:

(A) 10A, 10A
(B) 12A, 8A
(C) 14A, 6A
(D) 15A, 5A

Q. For high power rating appliances circuit having………………….current is used:

(A) 5A
(B) 10A
(C) 15A
(D) 20A

Q. In Fleming’s right hand rule direction in induced current is given by:

(A) thumb
(B) middle finger
(C) first finger
(D) none of these

Q. For a direct current generator to make contact with brushes……………..are used:

(A) solid rings
(B) split rings
(C) D.C commutator
(D) brushes

Q. To reverse direction of current in a motor …………………is used :

(A) sliding commutator
(B) solid commutator
(C) solid rings
(D) split ring commutator

Q. Magnetic field is measured in :

(A) newton meter
(B) Newton/Amp meter
(C) Ampere metre
(D) metre /Amp

Q. In the magnetic field the force acting on the current carrying conductor will  be maximum :

(A) If conductor is parallel to the field
(B) If conductor is perpendicular to the field
(C) If conductor subtends an angle of 60Deg with the field
(D) If conductor subtends an angle of 45deg with the field

Q. Electric motor converts electric energy into :

(A) Chemical energy
(B) Physical energy
(C) Mechanical energy
(D) heat energy

Q. Electric generator works on the principle :

(A) electromagnet induction principle
(B) on the principle of cell
(C) on the principle of resistance
(D) on the magnet induction principle

Q. The unit for measuring magnetic field is:

(A) web/m²
(B) web
(C) web m
(D) web/new

Q. A wire of length 10 cm is subjected to 3 Amp .current when placed perpendicular in a 2wb/m2 magnetic field then the value of magnetic force acting on the conductor will be :

(A) 0.6 Newton
(B) 0.06 Newton
(C) 6 Newton
(D) 6.2 Newton

Q. In Dynamo the direction of an electric current is measured by :

(A) Right hand rule
(B) left hand rule
(C) newton’s principle
(D) Electric principle

Q. Mechanical energy is converted into electric energy by :

(A) electric meter
(B) Ammeter
(C) voltmeter
(D) generator

Q. The direction of resultant force acting on the coil of electric motor is governed by :

(A) Fleming right hand rule
(B) Fleming left hand rule
(C) newton 2nd principle
(D) According to the to the Ampere rule

Q. When a current carrying solenoid is would over an iron core the core is called :

(A) an iron piece
(B) a core
(C) an electromagnet
(D) a permanent magnet

Q. Electromagnet induction is involved in :

(A) charging a body with a positive charge
(B) production of current by relative motion between a magnet and the coil
(C) rotation of the coil of an electric motor
(D) generation of magnet field due to a current carrying solenoid

Q. Which color wire is used for earthing ?

(A) Red
(B) Blue
(C) Green or yellow
(D) none of these

Q. Except iron another metal which is attracted by the magnet is :

(A) gold
(B) silver
(C) Nickel
(D) mercury

Q. Like poles:

(A) repel each other
(B) attract each other
(C) either attract or repel each other
(D) have no effects on each other

Q. Electromagnet induction was discovered by :

(A) H. Coersted
(B) Michael Faraday
(C) james van ellen
(D) thomas edison

Q. On increasing number of turns in a solenoid its magnetic effect :

(A) increases
(B) decreases
(C) remains same
(D) doubles

Q. Angle of declination at magnetic poles is :

(A) 90 deg
(B) 180 deg
(C) 270 deg
(D) 360 deg

Q. In houses color of live wire is :

(A) black
(B) red
(C) yellow
green

Q. Alnico is an alloy of:

(A) AL, Co, Fe
(B) Mg, Al, Zn, Co
(C) Co, Ni, Al
(D) Al, Ni, Sn

Q. Which of the following correctly describes the magnetic field near a long straight wire?

(A) The field consists of straight lines perpendicular to the wire.
(B) The field  consists of straight lines parallel to the wire.
(C) The field consists of radial lines originating from the wire.
(D) The field consists of concentric circles centered on the wire.

Q. The phenomenon of electromagnet induction is :

(A) the process of charging a body.
(B) the process of generating magnetic field due to a current passing through a coil.
(C) producing induced current in a coil due to relative motion between a magnet and the coil.
(D) the process of rotating a coil of an electric motor.

Q. The devices used for producing electric current is called a

(A) generator
(B) galvanometer
(C) ammeter
(D) motor

Q. The essential difference between an AC generator and a dc generator is that

(A) AC generator has an electromagnet while a DC generator has permanent magnet
(B) DC generator will generate a higher voltage
(C) AC generator will generate a higher voltage
(D) AC generate has slip rings while the DC generate has a commutator.

Q. At the time  of short circuit the current in the circuit.

(A) reduces substantially
(B) does not change
(C) increases heavily
(D) very continuously.