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Question
Two coils A and B of insulated wire are kept close to each other. Coil A is connected to a galvanometer while coil B is connected to a battery through a key. What would happen if:
the current is stopped by removing the plug from the key?
Explain your answer mentioning the name of the phenomenon involved.
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Solution
In this case, galvanometer pointer moves to other side. This shows that the direction of induced current is reversed and then quickly returned to zero.
This phenomenon is based on the principle of electromagnetic induction.
RELATED QUESTIONS
Consider a circular loop of wire lying in the plane of the table. Let the current pass through the loop clockwise. Apply the right-hand rule to find out the direction of the magnetic field inside and outside the loop.
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180°
A current flows in a wire running between the S and N poles of a magnet lying horizontally as shown in Figure below:
The force on the wire due to the magnet is directed:
fron N to S
from S to N
vertically downwards
vertically upwards
Two coils A and B of insulated wire are kept close to each other. Coil A is connected to a galvanometer while coil B is connected to a battery through a key. What would happen if:
a current is passed through coil B by plugging the key?
Explain your answer mentioning the name of the phenomenon involved.
A coil ABCD mounted on an axle is placed between the poles N and S of a permanent magnet as shown in Figure.
- In which direction will the coil begin to rotate when current is passed through the coil in direction ABCD by connecting a battery at the ends A and D of the coil?
- Why is a commutator necessary for continuous rotation of the coil?
- Complete the diagram with commutator, etc. for the flow of current in the coil?
State Fleming’s left-hand rule.
State whether a magnetic field is associated or not around a moving charge.
State under what conditions force acting on a current carrying conductor which is freely suspended in a magnetic field can be maximum.
A current flows in a wire running between the S and N poles of a magnet lying horizontally as shown in the figure below:
The force on the wire due to the magnet is directed ____________.
Which of the following factors affect the strength of force experience by current-carrying conduct in a uniform magnetic field?
The direction of force on a current carrying conductor in a magnetic field is given by ____________.
Describe the activity that shows that a current-carrying conductor experiences a force perpendicular to its length and the external magnetic field. How does Fleming’s left-hand rule help us to find the direction of the force acting on the current carrying conductor?
A simple motor is made in a school laboratory. A coil of wire is mounted on an axle between the poles of a horseshoe magnet, as illustrated.
In the example above, coil ABCD is horizontal and the battery is connected as shown.
- For this position, state the direction of the force on the arm AB.
- Why does the current in the arm BC not contribute to the turning force on the coil?
What do you know about Michael Faraday?
Assertion (A): A current carrying straight conductor experiences a force when placed perpendicular to the direction of magnetic field.
Reason (R): The net charge on a current carrying conductor is always zero.
