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प्रश्न
If ‘R’ is the radius of dees and ‘B’ be the magnetic field of induction in which positive charges (q) of mass (m) escape from the cyclotron, then its maximum speed (vmax) is _______.
A) `(qR)/(Bm)`
B)`(qm)/(Br)`
C) `(qBR)/m`
D) `m/(qBR)`
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उत्तर
`(qBR)/m`
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संबंधित प्रश्न
Explain different ways to induce current in a coil.
A horizontal straight wire 10 m long extending from east to west is falling with a speed of 5.0 m s−1, at right angles to the horizontal component of the earth’s magnetic field, 0.30 × 10−4 Wb m−2.
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- What is the direction of the emf?
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(b) brass
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(d) steel
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Describe different ways to induce current in a coil of wire.
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(c) the resistivity of the wire of the coil
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- Name the phenomenon.
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(a) Name the parts labeled A and B.
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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 .
(e) Sketch a graph showing how the p.d. across the ends of the rotating coil varies with time for an A.C. dynamo.
( 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
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the field and the number of turns constant,
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doubling the speed of rotation of the coil, keeping th e speed
constant.
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Transformer______.
A transformer has 400 turns in the primary winding and 10 turns in the secondary winding. The primary e.m.f. is 250 V and the primary current is 2.0 A. calculate:
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Name the following diagram and explain the concept behind it.

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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Write Fleming’s right hand thumb rule with the help of diagram.
Write the two names in the following diagram.
Right hand thumb rule.

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State Fleming’s right-hand rule.
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Based on your understanding of the phenomenon, answer the following question.
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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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