Moving Charges ...

The magnetic effect of electric current was discovered by

Two charges of same magnitude move in two circles of radii $$R_1\,  =\, R\, and\,  R_2\, =\, 2R$$ in a region of constant uniform magnetic field $$\vec{B}$$.
The work $$W_1\,  and\, W_2$$ done by the magnetic field in the Two cases, respectively are such that

A magnetic field can exert force on a

A proton and an $$\alpha$$ particle moving with the same speed enter a uniform magnetic field. The proton enters at right angles to the field. The magnetic force $$F$$ on the particles will be the same when the direction of motion of a particle is ________.

When the free ends of a tester are dipped into a solution, the magnetic needle shows deflection due to:

When a proton moves in a uniform magnetic field, the momentum change but its kinetic energy does not change because :

The pattern of the magnetic field around a conductor due to an electric current flowing through it depends on

If a current carrying wire carries 10A current then the magnetic field is X. Now the current in the wire increases to 100A, them magnetic field in the wire becomes

What is shape of magnet in moving coil galvanometer to make the radial magnetic field?

Positively charged particles are projected into a magnetic field. If the direction of the magnetic field is along the direction of motion of the charge particle, the particles get