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प्रश्न
State Fleming’s left-hand rule.
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उत्तर
Stretch the forefinger, middle finger, and the thumb of your left hand mutually perpendicular to each other. If the forefinger indicates the direction of the magnetic field and the middle finger indicates the direction of the current, then the thumb will indicate the direction of motion of the conductor.

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संबंधित प्रश्न
Imagine that you are sitting in a chamber with your back to one wall. An electron beam, moving horizontally from back wall towards the front wall, is deflected by a strong magnetic field to your right side. What is the direction of magnetic field?
State Fleming’s left hand rule.
Observe the following figure:

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What concealed do you get from the observation that a current-carrying wire deflects a compass needle placed near it?
Describe how you will locate a current-carrying wire concealed in a wall.
Draw a sketch to show the magnetic lines of force due to a current-carrying straight conductor.
State and explain the Clock face rule for determining the polarities of a circular wire carrying current.
State two ways to increase the force on a current-carrying conductor in a magnetic field.
The force exerted on a current-carrying wire placed in a magnetic field is zero when the angle between the wire and the direction of magnetic field is:
45°
60°
90°
180°
What is the force on a current-carrying wire that is parallel to a magnetic field? Give reason for your answer.
State condition when magnitude of force on a current carrying conductor placed in a magnetic field is zero?
How will the direction of force be changed, if the current is reversed in the conductor placed in a magnetic field?
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?
Name and state the rule of determine the direction of force experienced by a current carrying straight conductor placed in a uniform magnetic field which is perpendicular to it.
A flat coil ABCD is freely suspended between the pole of a U-shaped permanent magnet with the plane of coil parallel to the magnetic field.
Name an instrument which makes use of the principle stated above.
The shape of the magnetic field lines produced by a current-carrying conductor is ____________.
A magnetic field directed in north direction acts on an electron moving in east direction. The magnetic force on the electron will act ____________.
What does the direction of thumb indicate in the right-hand thumb rule. In what way this rule is different from Fleming’s left-hand rule?
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?
