JEE Mains · Physics · STD 12 -6. Electromagnetic induction
The magnetic field \(B\) crossing normally a square metallic plate of area \(4\,m ^2\) is changing with time as shown in figure. The magnitude of induced \(emf\) in the plate during \(t=2\,s\) to \(t=4\,s\), is \(..........\,mV\)
- A \(5\)
- B \(8\)
- C \(6\)
- D \(7\)
Answer & Solution
Correct Answer
(B) \(8\)
Step-by-step Solution
Detailed explanation
\(m =\tan \theta=\frac{10}{5}=2\) \(B = mt\) \(B =2 t\) \(\varepsilon=\left|\frac{ d \phi}{ dt }\right|=\frac{ d ( BA )}{ dt }=\frac{ AdB }{ dt }\) \(\varepsilon=\frac{4 d (2 t )}{ dt }=4 \times 2=8\,mVolt\)
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