JEE Main 202429 JanuaryMorning Shift
- Exam
- JEE Main
- Year
- 2024
- Date
- 29 January
- Shift
- Morning Shift
- Subject
- Physics
- Chapter
- Electromagnetic Induction
JEE Main 2024 · 29 January · Morning Shift · Physics · Electromagnetic Induction
A square loop of side 10cm and resistance 0 . 7Ω is placed...
A square loop of side and resistance is placed vertically in the east-west plane. A uniform magnetic field of is set up across the plane in the north-east direction. The magnetic field is decreased to zero in at a steady rate. Then, the magnitude of induced emf is . The value of is _______.
Correct answer
0
Step-by-step solution
The area vector for the square loop is given by
\overset{\to}{A} = ( 0 . 1{)}^{2}\overset{^}{j}{m}^{2}
According to the above diagram, the magnetic field is given by
\overset{\to}{B} = \dfrac{0 . 2}{\sqrt{2}}\overset{^}{i} + \dfrac{0 . 2}{\sqrt{2}}\overset{^}{j}
Hence, the magnitude of induced emf can be calculated as follows
\begin{cases}e & = & \dfrac{\Deltaϕ}{\Deltat} \\ & = & \dfrac{\overset{\to}{B} \cdot \overset{\to}{A} - 0}{1} \\ & = & \dfrac{\left(\dfrac{0 . 2}{\sqrt{2}}\overset{^}{i} + \dfrac{0 . 2}{\sqrt{2}}\overset{^}{j}\right) \cdot \left(( 0 . 1{)}^{2}\overset{^}{j}\right) - 0}{1}V \\ & = & \sqrt{2} \times {10}^{- 3}V\end{cases}
Hence, .