Home
Class 12
PHYSICS
A rectangular loop of length l and bread...

A rectangular loop of length `l` and breadth b is situated in a uniform magnetic field of induction B with its plane perpendicular to the field as shown in the figure . Calculate the rate of change of magnetic flux and the induced emf if the loop is rotated with constant angular velocity `omega`
(a) about an axis passing through the centre and perpendicular to the loop.
(b) about an axis passing through the centre parallel to the breadth through angle `180^(@)` .

Text Solution

Verified by Experts

(a) The flux linked through the loop at any instant is
`phi = "BA cos" theta `
`= Blb cos theta` = Blb= constant.
`:`. Rate of change of magnetic flux is
`(dphi)/(dt)= (d)/(dt) (Blb) implies (dphi)/(dt)=0 `
Hence induced e.m.f `epsilon = (dphi)/(dt) =0` .

(b) when the loop is rotated through `180^(@)` about an axis passing through centre and parallel to breadth the change in magnetic flux
`dphi = -Blb- (Blb)= -2Blb`.
`:.` The induced e.m.f
`e=-(dphi)/(dt) implies e= +(2Blb)/(pi//omega)`
`implies e= (2Blbomega)/(pi)`
Promotional Banner

Similar Questions

Explore conceptually related problems

A conducting square loop is placed in a magnetic field B with its plane perpendicular to the field. Now the sides of the loop start shrinking at a constant rate alpha. the induced emf in the loop at an instant when its side is a is

a semicircle wire of radius R is rotated with constant angular velocity about an axis passing through one end and perpendicular to the plane of wire. There is a uniform magnetic field of strength B . The induced emf between the ends is

a semicircle wire of radius R is rotated with constant angular velocity about an axis passing through one end and perpendicular to the plane of wire. There is a uniform magnetic field of strength B . The induced emf between the ends is

A circular loop of radius a having n turns is kept in a horizontal plane. A uniform magnetic field B exists in a vertical direction as shown in Fig.313. Find the emf induced in the loop if the loop is roated with a uniform angualr velocity omega about (a) an axis passing through the center and perendicular to the plane of the loop. (b) the diameter.

A rectangular loop of metallic wire is of length a and breadth b and carries a current i. The magnetic field at the centre of the loop is

A conducting loop rotates with constant angular velocity about its fixed diameter in a uniform magnetic field, whose direction is perpendicular to that fixed diameter.

A conducting loop rotates with constant angular velocity about its fixed diameter in a uniform magnetic field, whose direction is perpendicular to that fixed diameter.

A conducting circular loop is placed is a uniform magnetic field B =0.20 T with its plane perpendicular to the field . Somehow, the radius of the loop starts shrinking at a constant rate of 1.0 mm s^(-1) . Find the induced emf in the loop at an instant when the radius is 2 cm.

For an L shaped conducting rod placed in an uniform magnetic field vecB rotating with constant angular velocity omega about an axis passing through one of its ends A and normal to the plane of the conductor induced emf

A circular loop of wire is carring a current i (as shown in the figure). On applying a uniform magnetic field inward perpendicular to the plane of the loop, the loop