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OTI365 - NTSE - X Standard
NTSE SAT Physics - Magnetic Effects of Electric Current Model Questions

NTSE SAT Physics - Magnetic Effects of Electric Current

Exam Duration: 45 Mins Total Questions : 30

1 )

The direction of magnetic field at the centre of a coil carrying in clockwise direction

(a)
along the axis of the coil inwards
(b)
along the axis of the coil outwards
(c)
perpendicular to the axis
(d)
none of these

2 )

The phenomenon of electromagnetic induction was discovered by

(a)
Maxwell
(b)
Fleming
(c)
Faraday
(d)
Lenz

3 )

1 T equals

(a)
1 NA^-1m^-1
(b)
1 NAM²
(c)
1 NA^-1m^-2
(d)
1 N^-1Am

4 )

The wire with green plastic covering is

(a)
live wire
(b)
earth wire
(c)
neutral wire
(d)
none of these

5 )

Magnetic field produced at the centre of a current carrying circular wire is

(a)
Directly proportional to the square of the radius of the circular wire
(b)
Directly proportional to the radius of the circular wire
(c)
Inversely proportional to the square of the radius of the circular wire
(d)
Inversely proportional to the radius of the circular wire

6 )

The magnetic field lines inside a long, current carrying solenoid are nearly:

(a)
Straight
(b)
Circular
(c)
Parabolic
(d)
Elliptical

7 )

The direction of the force on a current-carrying wire placed in a magnetic field depends on:

(a)
The direction of the current
(b)
The direction of the field
(c)
The direction of current as well as field
(d)
Neither the direction of current nor the direction of field

8 )

Electromagnetic induction is the

(a)
Charging of a body with a positive charge
(b)
Production of current by relative motion between a magnet and a coil
(c)
Rotation of the coil of an electric motor
(d)
Generation of magnetic field due to a current carrying solenoid

9 )

When current is circular, the associated magnetic field is

(a)
Straight
(b)
Elliptical
(c)
Circular
(d)
Parabolic.

10 )

The electric device which works on the phenomenon of force on a current carrying conductor in a magnetic field is

(a)
Generator
(b)
Accelerator
(c)
Motor
(d)
Transformer.

11 )

In domestic electric circuits, fuse must be placed in series with

(a)
Earth wire
(b)
Neutral wire
(c)
Live wire
(d)
Any of the three wires

12 )

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 centred on the wire.

13 )

Which of the following instruments works by electromagnetic induction?

(a)
telephone receiver
(b)
simple motor
(c)
dynamo
(d)
moving coil galvanometer.

14 )

Potential difference between a live wire and the neutral wire is

(a)
200 volt
(b)
150 volt
(c)
210 volt
(d)
220 volt

15 )

The most important safety device method used for protecting electrical appliances from short circuiting or overloading is:

(a)
Earthing
(b)
Use of stabilizers
(c)
Use of electric meter
(d)
Use of fuse

16 )

Current flowing in conductors A and B is same, what is the ratio of the magnetic field produced around the conductor A at a distance of 5 cm from the conductor to the magnetic field produced around the conductor B at a distance of 2 cm from this conductor is

(a)
0.04
(b)
0.4
(c)
4.0
(d)
10

17 )

A positively charged particle say an alpha particle projected towards west is deflected towards north by a magnetic field. The direction of the magnetic field is:

(a)
Upward
(b)
Downward
(c)
Towards south
(d)
Towards east

18 )

Two parallel conductor carrying current in the same directions

(a)
Repel each other
(b)
Attract each other
(c)
Sometimes attract and sometimes repel each other
(d)
None of these

19 )

If the plug of the key is taken out (i.e. the circuit is made open) and magnetic field lines are drawn over the horizontal plane white sheet of paper, the lines are:

(a)
Concentric circles
(b)
Elliptical in shape
(c)
Straight lines parallel to. each other
(d)
Parabolic in shape

20 )

In these type of Questions, two statements are given. Choose the correct option by following directions given below:
(a) Statement I is correct and Statement II is correct explanation of the statement I.
(b) Statement I is correct but Statement II is not the correct explanation of the statement I.
(c) Statement I is true but statement II is not true.
(d) Statement I is not true but statement II is true.
Statement I: A soft iron bar placed inside a solenoid carrying current is magnetised.
Statement II: Magnetic field. inside a long solenoid carrying current is non-uniform.

(a)
A
(b)
B
(c)
C
(d)
D

21 )

Current can be made to flow through a coil without connecting the coil with a battery. Which of the following procedures would be most suited to test this fact?

(a)
Connect a galvanometer across the ends of the coil and observe if galvanometer shows a
deflection, when a bar magnet is placed near the one end of the coil.
(b)
Connect a galvanometer across the ends of the coil and observe if galvanometer shows a deflection, when a bar magnet is placed inside the coil.
(c)
Connect the galvanometer across the ends of the coil and observe if galvanometer shows a deflection, when a bar magnet is moved towards or away from the coil and along the axis of the coil.
(d)
Connect the galvanometer across the ends of the coil and observe if galvanometer shows a deflection, when a bar magnet is moved at right to the axis of the coil

22 )

The magnetic field at a point due to a current carrying conductor is directly proportional to

(a)
Resistance of the conductor
(b)
Thickness of the conductor
(c)
Current flowing through the conductor
(d)
(a) and (b) both

23 )

Two long parallel wires are at a distance of 1m.If both of them carry 1 A of current, them the force of attraction per unit length between the two wires is

(a)
2 x 10^-7 N m^-¹
(b)
2 x 10^-8 N m^-¹
(c)
5 x 10^-8 N m^-¹
(d)
5 x 10^-7 N m^-¹

24 )

A conductor of length I is moved perpendicular to uniform magnetic field B with velocity V as shown in figure.

(a)
zero
(b)
BIV
(c)
BIV/2
(d)
BI²V/2

25 )

An induction furnace works on the principle of

(a)
Self induction
(b)
Mutual induction
(c)
Eddy currents
(d)
Faraday's laws

26 )

The mutual inductance between two coils depends o

(a)
Medium between the coils only
(b)
Separation between two coils only
(c)
Both a and (b)
(d)
None of (a) and (b)

27 )

An electron moves along the time which lies in the same plane a circular loop of conducting wires. What will be the direction of the current induced in the loop if any?