Home
Class 12
PHYSICS
A circular coil of 100 turns and having ...

A circular coil of `100` turns and having a radius of `0*05m` carries a current of `0*1A`. Calculate the work required to turn the coil in an external magnetic field of `1*5T` through `180^@` about an axis perpendicular to the magnetic field. The plane of the coil is initially at right angles to the magnetic field.

Text Solution

Verified by Experts

The correct Answer is:
`0.24`
Here , n = 100 , r = 0.05 m I = 0.1 A
W = ? B = 1.5 T ,
`theta_(1)=0^(@)` (when plane of coil is at `90^(@)` to B )
`theta_(2) = 180^(@)`
M = NIA = NI `(pi r^(2))`
`= 100 xx 0.1 (3.14) (0.05)^(2) = 7.85 xx 10^(-2) "Am"^(2)`
` W = - MB (cos theta_(2)-cos theta_(1))`
` = - 7.85 xx 10^(-2) xx 1.5 (cos 180^(@) - cos 0^(@)) = 0.24 J `
Promotional Banner

Similar Questions

Explore conceptually related problems

A circular coil of 100 turns has an effective radius of 0.05 m and carries a current of 0.1 A. How much work is required to turn it in an external magnetic field of 1.5 Wb m^-2 through 180^@ about an axis perpendicular to the magnetic field. The plane of the coil is initially perpendicular to the magnetic field.

A circular coil of 100 turns and having an effective radius of 5cm carries a current of 0*1 ampere. How much work is required to turn it in an external magnetic field of 1*5 weber//m^2 through 180^@ about an axis perpendicular to magnetic field. The plane of the coil is initially perpendicular to the magnetic field.

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

A circular coil of 100 turns has a radius of 10 cm and carries a current of 5A. Calculate the magnetic field (a) at the centre of the coil (b) at a point on the axis of the coil at a distanceof 5cm from the centre of the coil.

A circular coil of 60 turns and radius 4 cm carries current of 1 A . How much work will be done in rotating the coil through 90^(@) . It is suspended freely in uniform magnetic field 0.2 T .

A circular coil having N turns and radius r carries a current I. It is held in the XZ plane in a magnetic field Bhati . The torque on the coil due to the magnetic field is :

A circular coil of radius 10 cm having 100 turns carries a current of 3.2 A. The magnetic field at the center of the coil is

A circular coil of wire consisting of 100 turns each of radius 8cm carries a current of 0.4A. What is the magnitude of magnetic field at the center of the coil

Calculate the torque on a 200 turns rectangular coil of length 20cm and breadth 10cm carrying a current of 10A , when placed in a magnetic field. The plane of the coil is making an angle of 60^@ with a magnetic field of 4T .

A circular coil of 0.2 m diameter has 100 turns and carries a current of 0.1 ampere. The intensity of magnetic field at the centre of the coil is -