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An electron accelerated through potential difference V passes through a uniform transverse magnetic field and experiences a force F. If the accelerating potential is increased to 2V, the electron in the same magnetic field will experience a force

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Important Questions on Moving Charges and Magnetism

MEDIUM

Two magnetic dipoles X and Y are placed at a separation d , with their axes perpendicular to each other. The dipole moment of Y is twice that of X . A particle of charge q is passing through their mid-point P , at angle θ=45o with the horizontal line, as shown in figure. What would be the magnitude of force on the particle at that instant? ( d is much larger than the dimension of the dipole)
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MEDIUM
A wire bent in the shape of a regular n polygonal loop carries a steady current I. Let l be the perpendicular distance of a given segment and R be the distance of a vertex both from the centre of the loop. The magnitude of the magnetic field at the centre of the loop is given by,
MEDIUM
The magnitude of the magnetic field at the centre of an equilateral triangular loop of side 1 m which is carrying a current of 10 A is:
[Take  μ0=4π×10-7 A-2 ]
MEDIUM
The electric fields of two plane electromagnetic plane waves in vacuum are given by E1=E0cosωt-kx j^ and E2=E0cosωt-ky k^, at t=0, a particle of charge q is at origin with a velocity v=08c j^ ( c is the speed of light in vaccum). The instantaneous force experienced by the particle is:
MEDIUM
An electron enters a chamber in which a uniform magnetic field is present as shown. 
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An electric field of appropriate magnitude is also applied so that the electron travels un-deviated without any change in its speed through the chamber. We are ignoring gravity. Then, the direction of the electric field is,
HARD
A very long wire ABDMNDC is shown in figure carrying current I. AB and BC parts are straight, long and at right angle. At D wire forms a circular turn DMND of radius R. AB, BC parts are tangential to circular turn at N and D. Magnetic filed at the center of circle is:
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EASY
A proton, a deuteron and an α-particle with same kinetic energy enter into a uniform magnetic field at right angle to magnetic field. The ratio of the radii of their respective circular paths is :
EASY
A charged particle moves through a magnetic field perpendicular to its direction. Then
EASY
The magnetic induction field has the dimensions of
MEDIUM
In a certain region static electric and magnetic fields exist. The magnetic field is given by B=B0i^+2j^-4k^. If a test charge moving with a velocity v=v03i^-j^+2k^ experiences no force in that region, then the electric field in the region, in SI units, is:
EASY
A charged particle carrying charge 1 μC is moving with velocity (2i^+3j^+4k^) m s-1. If an external magnetic field of (5i^+3j^-6k^)×10-3T exists in the region where the particle is moving then the force on the particle is F×10-9 N . the vector F is :
HARD
If one were to apply the Bohr model to a particle of mass 'm' and charge 'q' moving in a plane under the influence of a magnetic field 'B', the energy of the charged particle in the nth level will be:
MEDIUM
A particle of charge q and mass m is moving with a velocity -vi^(v0) towards a large screen placed in the Y-Z plane at distance d. If there is magnetic field B=B0k^, the minimum value of v for which the particle will not hit the screen is :
EASY
A circular coil of wire consisting of 100 turns each of radius 9 cm carries a current of 0.4 A. The magnitude of the magnetic field at the centre of coil is μ0=12.56×107 SI Units
EASY
The work done by a uniform magnetic field on a moving charge is,
HARD

An electron enters a magnetic field of 3 i^+4 j^ T with a velocity of 6 j^+4 k^ m s-1. The acceleration produced is

(em of electron =1.76×1011 C kg-1)

EASY

Consider a negatively charged particle moving with a velocity v in a magnetic field B applied perpendicular to the plane of the paper (into the paper). The particle follows the path A or B or C or D (shown in the figure)

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MEDIUM
An electron enters a chamber in which a uniform magnetic field is present as shown. Ignore gravity
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During its motion inside the chamber
MEDIUM
A particle of charge Q moves with a velocity v=ai^ in a magnetic field B=bj^+ck^ where a, b and c are constants. The magnitude of the force experienced by the particle is
MEDIUM

A square loop, carrying a steady current I, is placed in a horizontal plane near a long straight conductor carrying a steady current I1 at a distance d from the conductor as shown in the figure. The loop will experience
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