Question

The working of deflection magnetometer is based on
A. Tangent law
B. Curie – Weiss law
C. Ampere's law
D. Coulomb's law

Answer 1

Hint: We will start this question by first stating all the laws turn by turn, like, Tangent law, Curie – Weiss law, Ampere's law and Coulomb's law and then writing about the deflection magnetometer, like, its structure and its working. After that we will get the right answer to this question.

Complete step-by-step answer:
Tangent law of magnetism is a way to equate the powers of two magnetic fields perpendicular to each other. In other words - due to the horizontal component of the earth’s magnetic field, when a magnetic needle is freely suspended it comes to rest in the magnetic meridian plane.
In electromagnetism, one of the important laws is the Curie – Weiss law. It means that the magnetic susceptibility is above the Curie temperature point of a ferromagnet in the paramagnetic. The magnetic moment is a quantity of a magnet which determines its torque in an external magnetic field.
Ampere's law is also one of the most important laws in electromagnetism which relates the integrated magnetic field around a closed loop to the electric current passing through the loop. In other words, Ampere's law can be stated as, “the magnetic field created by an electric current is proportional to the size of that electric current with a constant of proportionality equal to the permeability of free space.”
Coulomb’s law is an electrical analogue of Newton’s law of Universal Gravitation in mechanics. It says that the force of attraction between two stationary points charges is:
(i) directly proportional to the product of the magnitude of the two charges, and
(ii) the distance between them is inversely proportional to the square.
With a small magnetic needle pivoting at the center of a circular scale, a deflection magnetometer consists of a large compass box therefore the needle can freely rotate in a horizontal plane. Reading of a scale at any point directly gives the distance of that point from the centre of the compass needle. Its working is based on the principle of Tangent law.
From above discussion it is clear that the working of a deflection magnetometer is based on the principle of Tangent law.
Hence, option A is the right answer.

Note: A magnetometer is a magnetism measuring devices – the frequency, power, or relative change of a magnetic field at a specific location. A compass is one of a device, in case of the Earth’s magnetic field which measures the direction of an ambient magnetic field.