Question 75: Electromagnetic Induction

Question

An emf of $$0.08 \mathrm{~V}$$ is induced in a metal rod of length $$10 \mathrm{~cm}$$ held normal to a uniform magnetic field of $$0.4 \mathrm{~T}$$, when moves with a velocity of:

Accepted Answer

The emf induced in a rod moving through a magnetic field is given by Faraday's law of electromagnetic induction, specifically, in the form of motional emf, which states that:
$ 	ext{emf} = B \cdot L \cdot v $
where:
(B) is the magnetic field strength,
(L) is the length of the rod, and
(v) is the velocity of the rod.
In this case, we are given the emf, (B), and (L), and we need to solve for (v). Rearranging the equation gives:
$ v = \frac{	ext{emf}}{B \cdot L} $
Substituting the given values:
$ v = \frac{0.08 \, 	ext{V}}{0.4 \, 	ext{T} 	imes0.1 \, 	ext{m}} = 2 \, 	ext{m/s} $

Answer

$$20 \mathrm{~ms}^{-1}$$

Answer

$$2 \mathrm{~ms}^{-1}$$

Answer

$$3.2 \mathrm{~ms}^{-1}$$

Answer

$$0.5 \mathrm{~ms}^{-1}$$

Electromagnetic Induction

An emf of $0.08 \mathrm{~V} is induced in a metal rod of length 10 \mathrm{~cm} held normal to a uniform magnetic field of 0.4 \mathrm{~T}$, when moves with a velocity of:

Choose the correct answer: