Which one of the following statements is true?

(a) A scalar quantity is the one that is conserved in a process.

(b) A scalar quantity is the one that can never take negative values.

(c) A scalar quantity is the one that does not vary from one point to another in space.

(d) A scalar quantity has the same value for observers with different orientations of the axes.

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.