### NEET Physics - New - Moving Charges and Magnetism

#### Question - 1

The magnetic field at a perpendicular distance of 2 cm from an infinite straight current carrying conductor is 2x10-6 T. The current in the wire is

• A 0.1 A
• B 0.2 A
• C 0.4 A
• D 0.8 A

#### Question - 2

A positive charge is moving towards an observer. The direction of magnetic induction lines is

• A clockwise
• B anticlockwise
• C right
• D left

#### Question - 3

If a copper wire carries a direct current, the magnetic field associated with the current will be

• A only outside the wire
• B only inside the wire
• C both inside and outside the wire
• D neither inside nor outside the wire

#### Question - 4

Current carrying wire produces

• A Only electric field
• B Only magnetic field
• C Both electric and magnetic field
• D None of the above

#### Question - 5

A circular coil of n turns and radius r carries a current I. The magnetic field at the centre is

• A $\frac { { \mu }_{ o }nI }{ r }$
• B $\frac { { \mu }_{ o }nI }{ 2r }$
• C $\frac { { 2\mu }_{ o }nI }{ r }$
• D $\frac { { \mu }_{ o }nI }{ 4r }$

#### Question - 6

A thin ring of radius R metre has charge q coulomb uniformly spread on it. The ring rotates about its axis with a constant frequency of f revolutions/s. The value of magnetic field induction in Wb/m2 at the centre of the ring is

• A $\frac { { \mu }_{ o }qf }{ 2\pi R }$
• B $\frac { { \mu }_{ o }q }{ 2\pi fR }$
• C $\frac { { \mu }_{ o }q }{ 2fR }$
• D $\frac { { \mu }_{ o }qf }{ 2R }$

#### Question - 7

A coil of wire has an area of 600 sq. cm and has 500 turns. If it carries 1.5 A current, its magnetic dipole moment is

• A 5 Am2
• B 15 Am2​​
• C 30 Am2
• D 45 Am2​​​​​​

#### Question - 8

Ampere's circuital law can be derived from

• A Ohm's law
• B Biot-Savart's law
• C Kirchhoff's law
• D Gauss's law

#### Question - 9

A circular coil carrying current behaves as a

• A bar magnet
• B horse shoe magnet
• C magnetic shell
• D solenoid

#### Question - 10

A long solenoid has n turns per metre and current I A is flowing through it. The magnetic field induction at the ends of the solenoid is

• A zero
• B ${ \mu }_{ o }nI/2$
• C ${ \mu }_{ o }nI$
• D $2{ \mu }_{ o }NI$