CBSE X Science Magnetic Effects of Current - EducareHut (Next Gen Knowledge Point)

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#1. If two circular coils can be arranged in any of the three situations as shown in the diagrams below, then their mutual induction will be:

Maximum in situation a

Maximum in situation b

Maximum in situation c

The same in all situations

#2. A.C generator works on the principle of

force experience by a conductor in magnetic field

electromagnetic induction

electrostatic

force experience by a charge particle in electric field.

Explanation: Generator works on principle of electromagnetic induction.

#3. Fleming’s left hand and Right hand rules are used in

Generator and electric motor

Electric motor and generator

any rule can be used for any device

both are not applied for generator and motor.

Explanation: Electric motor employs Fleming left hand rule while for generator, Fleming right-hand rule is used.

#4. The nature of magnetic field line passing through the centre of current carrying circular loop is

circular

ellipse

parabolic

straight line

Explanation:(d) magnetic field line at the centre of current carrying loop appears as a straight line.

#5. An electric motor is a device which transforms

Mechanical energy into electrical energy

Electrical energy into mechanical energy

Kinetic energy into potential energy

Electrical energy into Potential energy

#6. An electric generator actually acts as

a source of electric charge.

a source of heat energy.

an electromagnet.

a converter of energy.

#7. A soft iron bar is introduced inside a current carrying solenoid. The magnetic field inside the solenoid

will become zero.

will increase.

will decrease.

will remain unaffected.

#8. If the current values periodically from zero to a maximum value, back to zero and then reverses its direction, the current is

direct

alternative

pulsating

none of the answer

Explanation: The alternating current reverse its direction periodically.

#9. For a current in a long straight solenoid, N and S-poles are created at the two ends. Among the following statements, the incorrect statement is

The field lines inside the solenoid are in the form of straight lines, which indicates that the magnetic field is the same at all points inside the solenoid

The strong magnetic field produced inside the solenoid can be used to magnetise a piece of magnetic material like soft iron, when placed inside the coil

The pattern of the magnetic field associated with the solenoid is different from the pattern of the magnetic field around a bar magnet

The N and S-poles exchange position when the direction of current through the solenoid is reversed

Explanation: Option (a), (b) and (d) are correct. Only option (c) is incorrect because the pattern of magnetic fields due to solenoid and bar magnet is almost same.

#10. The main advantage of A.C power transmission over D.C power transmission over’ long distance is

AC transmit without much loss of energy

less insulation problem

less problem of instability

easy transformation.

Explanation: AC transmit over a long distance without much loss of energy as compare to DC.

#11. Choose the incorrect statement from the following regarding magnetic lines of field

The direction of magnetic field at a point is taken to be the direction in which the North Pole of a magnetic compass needle points

Magnetic field lines are closed curves

If magnetic field lines are parallel and equidistant, they represent zero field strength

Relative strength of magnetic field is shown by the degree of closeness of the field lines

Explanation: Parallel and equidistant magnetic field lines represent uniform and constant field strength.

#12. A fuse should always be placed in the

Live wire of the main circuit

Neutral wire of the main circuit

Earth wire of the main circuit

Both live and neutral wire of the main circuit.

#13. A positive charge is moving upwards in a magnetic field directed towards north. The particle will be deflected towards

west

north

south

east

Explanation: (a) Apply fleming’s left hand rule

#14. A magnetic field directed in north direction acts on an electron moving in east direction. The magnetic force on the electron will act

vertically upwards.

towards east.

vertically downwards.

towards north.

#15. When current is parallel to magnetic field, then force experience by the current carrying conductor placed in uniform magnetic field is

Twice to that when angle is 60°

Thrice to that when angle is 60°

zero

infinite

Explanation: (a) If the current direction is parallel to the magnetic field, then there will no force on the conductor exerted by the magnetic field.

#16. What should be the core of an electromagnet?

soft iron

hard iron

rusted iron

none of answer

#17. The condition for the phenomena of electromagnetic induction is that there must be a relative motion between

the galvanometer and magnet

the coil of wire and galvanometer

the coil of wire and magnet

the magnet and galvanometer

Explanation: (c) The relative motion between the magnet and coil of wire causes change in magnetic field lines linked with the coil to produces induced current if the circuit is closed.

#18. The north pole of Earth’s magnet is in the:

Geographical South

Geographical East

Geographical West

Geographical North

#19. Overloading is due to

Insulation of wire is damaged

fault in the appliances

accidental hike in supply voltage

All of the other 3 Answers

Explanation: All are the causes to occur overloading

#20. The shape of the magnetic field lines produced by a current carrying conductor are:

Straight lines

Concentric circles

Concentric ellipse

Concentric parabolas

#21. A positive charge is moving towards a person. The direction of magnetic field lines will be in

Clockwise direction

Anticlockwise direction

Vertically upward direction

Vertically downward direction

#22. Which of the following factors affect the strength of force experience by a current carrying conduct in a uniform magnetic field?

magnetic field strength

magnitude of current in a conductor

length of the conductor within magnetic field

All of the other 3 Answers.

Explanation: (d) All the factors affect the strength of magnetic force.

#23. Which device produces the electric current?

generator

galvanometer

ammeter

motor

#24. We can induce the current in a coil by

moving the coil in a magnetic field

by changing the magnetic field around it

by changing the orientation of the coil in the magnetic field

All of above

#25. A current through a horizontal power line flows from south to North direction. The direction of magnetic field line 0.5m above it is

North

South

West

East

Explanation:(a) Apply right-hand thumb rule.

Finish