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प्रश्न
Observe the given figure of Fleming’s Right Hand Rule and write the labels of A and B correctly.
उत्तर
- Label A: Direction of magnetic field
- Label B: Direction of induced current
APPEARS IN
संबंधित प्रश्न
A solenoid of length 1.5 m and 4 cm in diameter possesses 10 turns per metre. A current of 5 A is flowing through it. The magnetic induction at a point inside the solenoid along the axis is ............................. .
(μ0 = 4π × 10-7 Wb/Am)
- π × 10-5 T
- 2π × 10-5 T
- 3π × 10-5 T
- 4π × 10-5 T
State Fleming’s right-hand rule.
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.
The phenomenon of electromagnetic induction is
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- What is the instantaneous value of the emf induced in the wire?
- What is the direction of the emf?
- Which end of the wire is at the higher electrical potential?
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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?
The magnetic flux through a loop is varying according to a relation `phi = 6t^2 + 7t + 1` where `phi` is in milliweber and t is in second. What is the e.m.f. induced in the loop at t = 2 second?
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Explain why, an electromagnet is called a temporary magnet.
State the factors on which the strength of an electromagnet depends. How does it depend on these factors?
When current is 'switched on' and 'switched off' in a coil, a current is induced in another coil kept near it. What is this phenomenon known as?
What do you understand by the term "electromagnetic induction"? Explain with the help of a diagram.
How is the working of an electric bell affected, if alternating current be used instead of direct current?
Describe one experiment to demonstrate the phenomenon of electromagnetic induction.
The coil of a moving-coil galvanometer keeps on oscillating for a long time if it is deflected and released. If the ends of the coil are connected together, the oscillation stops at once. Explain.
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(b) The charge on C long after t = 0 is εC.
(c) The current in L just before t = t0 is ε/R.
(d) The current in L long after t = t0 is ε/R.
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A. C. generator______.
A coil has a self-inductance of 0·05 Henry. Find the magnitude of the emf induced in it when the current flowing through it is changing at the rate of 100 As-1.
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(ii) Give an explanation for your observation in (i).
(iii) State the rule, which will help you to find the motion of rotation of coil.
(iv) In which position will the coil ultimately come to rest?
(v) State four ways of increasing the magnitude of force acting on the coil.
Write the two names in the following diagram.
Fleming’s right hand rule.
State Lenz’s law.
Give an illustration of determining direction of induced current by using Lenz’s law.
Show that Lenz’s law is in accordance with the law of conservation of energy.
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A cylindrical bar magnet is kept along the axis of a circular coil. If the magnet is rotated about its axis, then ____________.
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If the sun radiates energy at the rate of 3.6 × 1033 ergs/sec the rate at which the sun is loosing mass is given by ______.
Induced current flows through a coil ______.
Which of the following instruments works by electromagnetic induction?
A galvanometer is an instrument that can detect the presence of a current in a circuit.
Which of the following phenomena makes use of electromagnetic induction?
A current I = 10 sin(100π t) A is passed in first coil, which induces a maximum e.m.f of 5π volt in second coil. The mutual inductance between the coils is ______.
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(R1 and R2 are radii of CD and EF respectively. l = current in the loop, μ0 = permeability of free space)
