Advertisements
Advertisements
प्रश्न
A pair of adjacent coils has a mutual inductance of 1.5 H. If the current in one coil changes from 0 to 20 A in 0.5 s, what is the change of flux linkage with the other coil?
Advertisements
उत्तर
We are interested in the flux change associated with coil 2 as the current in coil 1 changes from 0 to 20 A.
∅2 = MI1
and Δ∅2 = MΔI1
Δ∅2 = 1.5 [20 – 0]
or Δ∅2 = 30 Wb
Here, the current is increasing, so the change in flux density will oppose the increase in current.
APPEARS IN
संबंधित प्रश्न
Ram is a student of class X in a village school. His uncle gifted him a bicycle with a dynamo fitted in it. He was very excited to get it. While cycling during night, he could light the bulb and see the objects on the road. He, however, did not know how this device works. he asked this question to his teacher. The teacher considered it an opportunity to explain the working to the whole class.
Answer the following questions:
(a) State the principle and working of a dynamo.
(b) Write two values each displayed by Ram and his school teacher.
A square loop MNOP of side 20 cm is placed horizontally in a uniform magnetic field acting vertically downwards as shown in the figure. The loop is pulled with a constant velocity of 20 cm s−1 till it goes out of the field.

(i) Depict the direction of the induced current in the loop as it goes out of the field. For how long would the current in the loop persist?
(ii) Plot a graph showing the variation of magnetic flux and induced emf as a function of time.
The current flowing through an inductor of self inductance L is continuously increasing. Plot a graph showing the variation of
Magnetic flux versus the current
How does the mutual inductance of a pair of coils change when
(i) distance between the coils is increased and
(ii) number of turns in the coils is increased?
A metallic loop is placed in a nonuniform magnetic field. Will an emf be induced in the loop?
Find magnetic flux density at a point on the axis of a long solenoid having 5000 tums/m when it carrying a current of 2 A.
Answer the following question.
When a conducting loop of resistance 10 Ω and area 10 cm2 is removed from an external magnetic field acting normally, the variation of induced current-I in the loop with time t is as shown in the figure.
Find the
(a) total charge passed through the loop.
(b) change in magnetic flux through the loop
(c) magnitude of the field applied

Two inductors of inductance L each are connected in series with the opposite? magnetic fluxes. The resultant inductance is ______.
A cylindrical bar magnet is rotated about its axis (Figure). A wire is connected from the axis and is made to touch the cylindrical surface through a contact. Then

A coil is placed in a time varying magnetic field. If the number of turns in the coil were to be halved and the radius of wire doubled, the electrical power dissipated due to the current induced in the coil would be: (Assume the coil to be short circuited.)
A circular coil has radius ‘r', number of turns ‘N’ and carries a current ‘I’. Magnetic flux density ‘B’ at its centre is ______.
Which symbol represents magnetic flux?
What is \[\theta\] in \[\Phi_B=BA\cos\theta\]?
How is a surface handled when calculating flux through a non-uniform magnetic field or a curved surface?
Which equivalent unit of magnetic flux uses volt and second?
What is the nature of magnetic flux?
Which expression relates induced emf to the change in magnetic flux for a coil of \[N\] turns?
Which expression is Gauss's Law for Magnetism?
