An emf is induced whenever there is a change in the magnetic field linked with electric circuits. This is stated by the:

Correct option is D

The correct answer is option ( b ) Faraday's law.

Faraday's Law of Electromagnetic Induction

Faraday's law explains that an electromotive force (EMF) is induced in a circuit whenever there is a change in the magnetic flux linked with it. Mathematically, the induced EMF $$(\mathcal{E})$$​ is proportional to the rate of change of magnetic flux $$(\Phi_B​)$$​ :

​$$\mathcal{E} = - \frac{d\Phi_B}{dt}​​$$​​

The negative sign in the equation is due to Lenz's Law, which states that the direction of the induced EMF always opposes the change in magnetic flux that caused it.

Information booster :

Ohm's Law states that the current ( I ) flowing through a conductor between two points is directly proportional to the voltage (V) across the two points and inversely proportional to the resistance ( R ) of the conductor.

It is mathematically expressed as:

V = I ⋅ R

Where:

• V is the voltage
• I is the current
• R is the resistance

Gravitation’s law states that every particle of matter in the universe attracts every other particle with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers.

It is mathematically expressed as:

​$$F = G \frac{m_1 m_2}{r^2}$$​​

Where:

• F is the gravitational force,
• G is the gravitational constant,
• $$m_1​$$​ and $$m_2$$​ are the masses of the two objects,
• r is the distance between their centers.

Newton's Laws of Motion are:

• First Law (Law of Inertia): A body at rest remains at rest, and a body in motion remains in uniform motion unless acted upon by an external force.
• Second Law: The acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass.

F = ma

Where F is force, m is mass, and a is acceleration.

• Third Law: For every action, there is an equal and opposite reaction.