MEDIUM
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A rectangular loop PQMN with movable arms PQ of length 10 cm and resistance 2 Ω is placed in a uniform magnetic field of 0.1 T acting perpendicular to the plane of the loop as is shown in the figure.

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The resistance of the arm MN, NP and MQ are negligible. Calculate the EMF induced in the arm PQ and the current induced in the loop when arm PQ is moved with velocity 20 m s-1.

Important Questions on Electromagnetism

MEDIUM

What do you mean by electromagnetic induction? Name the two great experimentalists who carried long series of experiments on electromagnetic induction. You are given two coils one galvanometer, one battery and some connecting wires. Describe a experiment that can show the production of electromagnetic induction.

 

EASY
Explain the two different ways to induce a current in the coil.
EASY
If a coil of metal wire is kept stationary in a uniform magnetic field, then_______.
MEDIUM
In which of the following situation does the current will be induced?
MEDIUM

A magnet kept at the centre of two coils A and B is moved  to and fro as shown in the diagram. The two galvanometers show deflection.

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State with a reason whether: x>y  or x<y [x and y are magnitudes of deflection]

MEDIUM

Observe the given diagram. Explain the experiment related to this diagram. What conclusions can be drawn from this experiment?

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EASY
What do you mean by electromagnetic induction?
MEDIUM
A uniform magnetic field is restricted within a region of radius,  r. The magnetic field changes with time at a rate, dBdt. Loop one of radius R>r encloses the region, r and loop two of radius, R is outside the region of magnetic field as shown in the figure below. Then the emf generated is

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HARD

An infinitely long straight wire carrying current I, one side opened rectangular loop and a conductor C with a sliding connector are located in the same plane, as shown in the figure. The connector has length l and resistance R. It slides to the right with a velocity v. The resistance of the conductor and the self-inductance of the loop are negligible. The induced current in the loop, as a function of separation r, between the connector and the straight wire is:

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HARD

A 1 m long thin metal bar of negligible resistance weighing 1 kg rests on two metal supports as shown in the figure. The supports are connected in series to an ideal cell and a resistance. A uniform magnetic field 0.5 T is applied in the region normal to the plane of the paper and into the paper. Maximum emf that the cell can have without breaking the circuit in volt is
(Acceleration due to gravity =10 m s-2 )

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EASY
What is an electromagnet? How does solenoid behave like a magnet?
HARD

A square-shaped conducting wire loop of dimension a moving parallel to the x-axis approaches a square region of size b(a<b) where a uniform magnetic field B exists pointing into the plane of the paper (see figure). As the loop passes through this region, the plot correctly depicting its speed (v) as a function of x is.

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MEDIUM
What do you mean by electromagnetic induction? Explain the use of Fleming’s right-hand rule in finding the direction of current induced in the conductor.
MEDIUM

What is electromagnetic induction? A coil of insulated copper wire is connected to a galvanometer. What will happen in the galvanometer if a bar magnet is (a) pushed into the coil, (b) withdrawn from inside the coil, (c) held stationary inside the coil.

MEDIUM
A thin diamagnetic rod is placed vertically between the poles of an electromagnet. When the current in the electromagnet is switched on, then the diamagnetic rod is pushed up, out of the horizontal magnetic field. Hence, the rod gains gravitational potential energy. The work required to do this comes from
HARD
A bar magnet falls with its north pole pointing down through the axis of a copper ring. When viewed from above, the current in the ring will be
MEDIUM
The figure shows a bar magnet and a metallic coil. Consider four situations. (I) Moving the magnet away from the coil. (II) Moving the coil towards the magnet. (III) Rotating the coil about the vertical diameter. (IV) Rotating the coil about its axis.

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An emf in the coil will be generated for the following situations.
EASY
The change in magnetic field lines in a coil is the cause of induced electric current in it. Name the underlying phenomenon.
MEDIUM
A conducting bar of mass m and length l moves on two frictionless parallel rails in the presence of a constant uniform magnetic field of magnitude B directed into the page as shown in the figure.The bar is given an initial velocity v0 towards the right at t=0.
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Then, the
EASY
An electron moves on a straight line path XY as shown. The abcd is a coil adjacent to the path of electron. What will be the direction of current, if any, induced in the coil?

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