Question

What the magnetic field (B)and the induced current if the moving rod in magnetic field is 2 mm long, the velocity v-40 cm/s, the total resistance of loop is 0.50 and the motional (emf) is 0.3 Volt?

Answer 1

Given:

Moving rod in magnetic field is 2 mm long, the velocity v-40 cm/s, the total resistance of loop is 0.50 and the motional (emf) is 0.3 Volt.

To find:

Magnetic field and induced current?

Calculation:

Let induced current be i :

$\rm \: i = \dfrac{e}{r} = \dfrac{0.3}{0.5} = 0.6 \: amp$

Now, we know that motional emf is given as:

$\rm \: e = L \times v \times B$

• Put values in SI UNITS:

$\rm \implies\: 0.3= \dfrac{2}{1000} \times 0.4\times B$

$\rm \implies\: B = \dfrac{300}{0.8}$

$\rm \implies\: B = 375 \: T$

So, magnetic field intensity is 375 Tesla.