An electron makes (`3 xx 10^5)` revolutions per second in a circle of radius 0.5 angstrom. Find the magnetic field B at the centre of the circle.

An electron moves in a circular orbit with a uniform speed v. It produces a magnetic field B at the centre of the circle. Prove that the radius of the circle is proportional to sqrt(V/B) .

A chord of a circle of radius 6cm is making an angle 60 ^(@) at the centre.Find the length of the chord.

In the Bohr model of hydrogen atom, the electron is treated as a particle going in a circle with the centre at the proton. The proton itself is assumed to be fixed in an inertial frame. The centripetal force is provided by the Coloumb attraction. In the ground state, the electron goes round the proton in a circle of radius 5.3xx10^-11m . Find the speed of the electron in the ground state. Mass of the electron =9.1xx10^-31 kg and charge of the electron = 1.6xx10^-19C .

A bar magnet of length 1cm and cross-sectonal area 1.0 cm^2 produces a magnetic field of 1.5 xx 10^(-4) T at a point in end-on position at a distance 15cm away from the centre. (a) Find the magnetic moment M of the magnet. (b) Find the magnetization I of the magnet. (c) Find the magnetic field B at the centre of the magnet.

A 2 mu C charge moving around a circle with a frequency of 6.25 xx 10^(12) Hz produces a mganetic field 6.28 tesla at the centre of the circle. The radius of the circle is

The ends of diameter of a circle are (2,3) and (6,5) . The centre of the circle is

An electorn moves in a circle of radius 10cm with a constant speed of 4.0xx10^(6)ms^(-1) .Find the electric current at a point on the circle.

A hydrogen atom contains one proton and one electron. It may be assumed that the electron revolves in a circle of radius 0.53 angstrom (1 angstrom = 10^(-10) m and is abbreviated as A) with the proton at the centre. The hydrogen atom is said to be in the ground state in this case. Find the magnitude of the electric force between the proton and the electron of a hydrogen atom in its ground state.

A hydrogen atom contains one proton and one electron. It may be assumed that the electron revolves in a circle of radius 0.53 angstrom (1 angstrom = 10^(-10) m and is abbreviated as A) with the proton at the center. The hydrogen atom is said to be in the ground state in this case. Find the speed of the electron in the ground state of hydrogen atom.