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प्रश्न
State Fleming’s right-hand rule.
उत्तर
Fleming’s right-hand rule:-
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 motion of the conductor, then the middle finger will show the direction of the induced current.
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संबंधित प्रश्न
When a bar magnet is pushed towards (or away) from the coil connected to a galvanometer, the pointer in the galvanometer deflects. Identify the phenomenon causing this deflection and write the factors on which the amount and direction of the deflection depends. State the laws describing this phenomenon.
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B = − B0 k (r ≤ a; a < R)
= 0 (otherwise)
What is the angular velocity of the wheel after the field is suddenly switched off?
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Name two devices in which electromagnets are used and two devices where permanent magnets are used.
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(a) north pole
(b) east pole
(c) south pole
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- Name the phenomenon.
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(b) The charge on C long after t = 0 is εC.
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(b) How can you reverse the direction of rotation of the armature?
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(c) Which of the output terminals is positive if the coil is rotating in the
direction shown in the diagram (anticlockwise)?
( d ) What is the position of the rotating coil when p.d. across its ends is zero? Explain why p.d. is zero when the coil is at this position .
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( f) On th e same sheet of paper and vertically below the first graph using the same time scale, sketch graphs to show the effect of
(i) Doubling the speed of rotation and at the same time keeping
the field and the number of turns constant,
(ii ) Doubling the number of turns on the coil and at the same time
doubling the speed of rotation of the coil, keeping th e speed
constant.
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(a) The secondary voltage,
(b) The secondary current, assuming 100% efficiency.
Name the following diagram and explain the concept behind it.
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Draw a labelled diagram to make an electromagnet from a soft iron bar. Mark the polarity at its ends in your diagram. What precaution would you observe while making it?
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Right hand thumb rule.
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Ansari Sir was demonstrating an experiment in his class with the setup as shown in the figure below.
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Based on your understanding of the phenomenon, answer the following question.
What is the principle which Ansari Sir is trying to demonstrate?
Ansari Sir was demonstrating an experiment in his class with the setup as shown in the figure below.
A magnet is attached to a spring. The magnet can go in and out of the stationary coil. He lifted the Magnet and released it to make it oscillate through the coil.
Based on your understanding of the phenomenon, answer the following question.
Consider the situation where the Magnet goes in and out of the coil. State two changes which could be made to increase the deflection in the galvanometer.
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The working of a dynamo is based on the principle of
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