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प्रश्न
State Fleming’s Right Hand Rule.
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उत्तर
- Stretch the thumb, forefinger and middle finger of the right hand so that they are perpendicular to each other.
- If the forefinger indicates the direction of the magnetic field and the thumb shows the direction of the motion of the conductor, then the middle finger will show the direction of the induced current.
- The induced current is found to be the maximum when the direction of motion of the coil is at right angles to the magnetic field.
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संबंधित प्रश्न
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(a)`sigma / in_0[R/r]^2`
(b)`in_0/sigma[R/r]^2`
(c)`R/r[sigma/in_0]^2`
(d)`R/sigma[r/in_0]^2`
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State Fleming’s right-hand rule.
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The most suitable material for making the core of an electromagnet is:
(a) soft iron
(b) brass
(c) aluminium
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What do you understand by the term "electromagnetic induction"? Explain with the help of a diagram.
When the magnet shown in the diagram below is moving towards the coil, the galvanometer gives a reading to the right.
() What is the name of the effect being produced by the moving magnet?
(2) State what happens to the reading shown on the galvanometer when the magnet is moving away from the coil.
(3) The original experiment is repeated. This time the magnet is moved towards the coil at a great speed. State two changes you would notice in the reading on the galvanometer.
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A. C. generator______.
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Using Ampere's law, obtain an expression for the magnetic induction near a current-carrying straight infinitely long wire.
Observe the given figure of Fleming’s Right Hand Rule and write the labels of A and B correctly.
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Write the two names in the following diagram.
Fleming’s right hand rule.
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A 50 cm long solenoid has 400 turns per cm. The diameter of the solenoid is 0.04 m. Find the magnetic flux linked with each turn when it carries a current of 1 A.
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A coil of one turn is made of a wire of certain length and then from the same length, a coil of two turns is made. If the same current is passed in both the cases, then the ratio of the magnetic inductions at their centres will be:
AB is a coil of copper wire having a large number of turns. The ends of the coil are connected with a galvanometer as shown. When the north pole of a strong bar magnet is moved towards end B of the coil, a deflection is observed in the galvanometer.
- State the reason for using galvanometer in the activity and why does its needle deflects momentarily when magnet is moved towards the coil.
- What would be observed in the galvanometer in a situation when the coil and the bar magnet both move with the same speed in the same direction? Justify your answer.
- State the conclusion that can be drawn from this activity.
Will there be any change in the momentary deflection in the galvanometer if number of turns in the coil is increased and a more stronger magnet is moved towards the coil?
OR
What is electromagnetic induction? What is observed in the galvanometer when a strong bar magnet is held stationary near one end of a coil of large number of turns? Justify your answer.
