Exercise

Find the potential difference across $2 \mathrm{\mu F}$ in steady state.

A neutron, a proton, an electron and an $\mathrm{\alpha }$-particle enter a region of uniform magnetic field with the same velocities. The magnetic field is perpendicular and directed into the plane of the paper. The tracks of the particles are labelled in the fig

The electron follows the track

The de-Broglie wavelength associated with electrons revolving round the nucleus in a singly ionised helium atom in first excited state, will be

A coil of inductance $0.50 \mathrm{H}$ and resistance $100 \mathrm{\Omega }$ is connected to a $240 \mathrm{V}, 50 \mathrm{Hz}$ a.c. supply.

(i) What is the maximum current in the coil?

(ii) What is the time lag between the voltage maximum and the current maximum.

What is the force between the two charges  of magnitudes $10 \mathrm{C}$ and $25 \mathrm{C}$ placed at $(1,0,5)$ and $(-2,3,3)$ respectively.

The effective resistance between points A and B of the network shown in figure is

For the given circuit, find the current through $1 \mathrm{\Omega }$, $2 \mathrm{\Omega }$ and $3 \mathrm{\Omega }$  resistors.

The refractive index of material of a particular optical fibre is $1.75$. At what maximum angle a ray can be made incident on it, so that it is totally internally reflected? Consider air as an external medium with refractive index as $1.0$.