Moving Charges and Magnetism

Related Questions

• A straight wire of length $({\pi ^2})$ metre is carrying a current of $2A$ and the magnetic field due to it is measured at a point distant 1 cm from it. If the wire is to be bent into a circle and is to carry the same current as before, the ratio of the magnetic field at its centre to that obtained in the first case would be

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• A long solenoid has 200 turns per cm and carries a current of 2.5 amps. The magnetic field at its centre is$({\mu _0} = 4\pi \times {10^{ - 7}}\,weber/amp{\rm{ - }}m)$

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• The coil of a galvanometer consists of 100 turns and effective area of 1 square cm. The restoring couple is ${10^{ - 8}}\,N - m/radian$. The magnetic field between the pole pieces is 5 T. The current sensitivity of this galvanometer will be

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• An electron, a proton, a deuteron and an alpha particle, each having the same speed are in a region of constant magnetic field perpendicular to the direction of the velocities of the particles. The radius of the circular orbits of these particles are respectively $R_e$, $R_p$, $R_d$ and $R_\alpha$. It follows that

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• If a particle of charge ${10^{ - 12}}\,coulomb$ moving along the $\hat x -$ direction with a velocity ${10^5}\,m/s$ experiences a force of ${10^{ - 10}}\,newton$ in $\hat y -$ direction due to magnetic field, then the minimum magnetic field is

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