Physics-
General
Easy
Question
The variation of induced emf (E) with time (t) in a coil if a short bar magnet is moved along its axis with a constant velocity is best represented as
The correct answer is:
As the magnet moves towards the coil, the magnetic flux increases (nonlinearly). Also there is a change in polarity of induced emf when the magnet passes on to the other side of the coil.
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The graph Shows the variation in magnetic flux 
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The graph Shows the variation in magnetic flux with time through a coil. Which of the statements given below is not correct
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A rectangular loop with a sliding connector of length l = 1.0 m is situated in a uniform magnetic field B = 2T perpendicular to the plane of loop. Resistance of connector is r = 2
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Plane figures made of thin wires of resistance R = 50 milli ohm/metre are located in a uniform magnetic field perpendicular into the plane of the figures and which decrease at the rate dB/dt = 0.1 m T/s. Then currents in the inner and outer boundary are. (The inner radius a = 10 cm and outer radius b = 20 cm)
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Shown in the figure is a circular loop of radius r and resistance R. A variable magnetic field of induction 
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The resistance in the following circuit is increased at a particular instant. At this instant the value of resistance is 10. The current in the circuit will be now
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A conducting rod PQ of length L = 1.0 m is moving with a uniform speed v = 2 m/s in a uniform magnetic field 
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Physics-General
