4.20 A magnetic field set up using Helmholtz coils (described in Exercise 4.16) is uniform in a small region and has a magnitude of 0.75 T. In the same region, a uniform electrostatic field is maintained in a direction normal to the common axis of the coils. A narrow beam of (single species) charged particles all accelerated through 15 kV enters this region in a direction perpendicular to both the axis of the coils and the electrostatic field. If the beam remains undeflected when the electrostatic field is 9.0 * 10^–5 V m^–1, make a simple guess as to what the beam contains. Why is the answer not unique?

There are two types of electricity - static and current. The current electricity is divided into Alternating Current (AC) and Direct Current (DC). Based on the production methods, electricity is divided into - heat, chemical, pressure, light and magnetism.

There are four types of power supply - switch-mode power supplies, linear power supplies, linear power supplies, and programmable power supplies

According to this law, at any point, magnetic field due to a tiny current element is directly proportional to the current element length.

Tesla (T) is the SI unit of magnetic field. Tesla is named after Nikola Tesla.

The different types of magnetism are - Diamagnetism, Paramagnetism, and Ferromagnetism.