Electricity and Magnetism Answers

Use Ampere's law for steady currents to derive the magnetic field due to a solenoid.
Four very long straight wires are closely bound together to form a small cable.
Currents carried by the wires are : I1 =15A, 12 = -10A, 13 = 20A and 14 = - 5A.
Determine B at a distance of 5 cm from the cable.

The electric field of a plane electromagnetic wave is given by
Ex = 0, Ey =100 cos(4π x 10^8 t — πX/3)
Ez = 0 where E is in Vm^-1, t is in seconds and x is in meters.
Determine v, k, X, direction of propagation of the wave and the direction of the magnetic field.

Discuss briefly the behaviour of a dielectric in an electric field and explain the concept of polarisation.

A beam of electrons passes undeflected through mutually perpendicular electric and magnetic fields of magnitudes 6 kVm^-1 and 10^-3 T, respectively. By maintaining the same magnetic field when the electric field is cut off, the electrons move in the magnetic field in a circular path. Calculate the speed of electrons and the radius of the circular path.

A uniform plane wave has a wavelength of 6cm in vacuum and 2 cm in a non-magnetic dielectric having permeability of free space. Calculate the dielectric constant of the dielectric and the phase velocity of propagation of the wave through it.

Define the inductive time constant of an LR circuit. An inductance coil L, a resistor R and a battery are connected in series. The time constant of the circuit is 3.5 x 10^-3 s.
When a resistance of 6 ohm is added in series, a new time constant of 1.5 x 10^-3 s is obtained. Calculate the inductance of the coil and the resistance of the resistor.

Obtain an expression for the drift velocity of electrons in a metallic conductor.

What are electrolytic capacitors ? Mention
its different types.

Can energy be created or destroyed?

Ellen electron y protus proton are traveling through space in a straight line at a distance of 1cm from each other, when suddenly it gets in contact with an magnetic field with a magnetic indudction of 1T. If we assume that they are equally charged and perpendicular to the field, what is the velocity of the particles?