Question

Calculate the maximum emf induced when a square frame is making $240\, r.p.m$ each side of square being $20 cm$ and magnetic field intensity is $500\,$ gauss?

• A. $5.01 \times 10^{-2} V$
• B. $5.02 \times 10^{-2} V$
• C. $5.03 \times 10^{-2} V$
• D. $8 \times 10^{-3} V$

Answer 1

Answer: (B)

As we know
$ e = NAB \omega $
$e =1 \times\left(20 \times 10^{-2}\right)^{2} \times 500 \times 10^{-4} \times 2 \pi \times \frac{240}{60} $
$e =400 \times 10^{-4} \times 500 \times 10^{-4} \times 2 \pi \times 4 $
$e =20 \times 4 \times 10^{-4} \times 2 \pi $
$=80 \times 10^{-4} \times 2 \pi $
$e =5.02 \times 10^{-2} V$