# Magnetic Effects of Electric Current and Magnetism

## Magnetic Effects of Electric Current and Magnetism Notes for Class 11 - 12

**Ampere's Law**

The line integral of the magnetic field in a continuous closed path or loop is µ₀ times the total electric current passed in the region enclosed by the path.

**Tesla**

When 1 coulomb of charge moves at a velocity of 1 ms^{-1} perpendicularly to the direction of a magnetic field experiencing 1 N of force, the magnetic of that magnetic field is called 1 tesla (T).

**Hall effect and Hall voltage**

When an electric conductor is set up perpendicularly at a magnetic field, a potential difference develops perpendicular to both electric current and magnetic field. This is the Hall effect and the produced potential difference is called voltage or Hall voltage.

**Magnetic Axis**

An imaginary line joining the two poles of a terrestrial magnet is called the magnetic axis.

**Magnetic Middle Plain**

The imaginary plane perpendicular to the magnetic axis at the midpoint is called the magnetic middle plane.

**Geographical axis**

An imaginary line joining the two geographical poles is called the geographical axis.

**Geographical middle plain**

An imaginary perpendicular plain at the midpoint of the geographical axis is called the geographical middle plain.

**The horizontal component of the terrestrial magnetic field **

The component of the terrestrial magnetic field at any point along the horizontal line is called the horizontal component (H) at the particular point of that field.

**Hysteresis**

From the H-I graph, it is observed that the intensity of magnetization (I) is always lower than the intensity (H). This phenomenon is called hysteresis.