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प्रश्न
For Fleming's left-hand rule, write down the three things that are 90° to each other, and next to each one write down the finger or thumb that represents it.
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उत्तर
In Fleming's left-hand rule, when thumb, forefinger and central finger are kept mutually perpendicular to each other:
(a) Thumb represents force.
(b) Forefinger represents magnetic field.
(c) Central finger represents current.
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संबंधित प्रश्न
Which of the following property of a proton can change while it moves freely in a magnetic field? (There may be more than one correct answer.)
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What is a solenoid? Draw a sketch to show the magnetic field pattern produced by a current-carrying solenoid.
What type of core should be put inside a current-carrying solenoid to make an electromagnet?
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(a) will decrease
(b) will increase
(c) will become zero
(d) will remain the same
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45°
60°
90°
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
Which way does the wire in the diagram below tend to move?
What is the force on a current-carrying wire that is parallel to a magnetic field? Give reason for your answer.
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.
Name and state the law which is used to determine the direction of force on a current carrying conductor placed in a magnetic field.
i) Which principle is explained in this figure?
ii) Which rule is used to find out the direction of a force in this principle?
iii) In which machine this principle is used? Draw a diagram showing working of that machine

A flat coil ABCD is freely suspended between the pole pieces of a U-shaped permanent magnet with the plane of coil parallel to the magnetic field.
When will the couple acting on the coil be
- maximum
- minimum?
State whether a magnetic field is associated or not around a moving charge.
A magnetic field directed in north direction acts on an electron moving in east direction. The magnetic force on the electron will act ____________.
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?
