The figure given below shows a square-shaped loop MNOP of side \(25\text{ cm}\) placed horizontally in a uniform magnetic field \(\vec{B}\) directed vertically downward. The position of the loop at \(t = 0\text{ s}\) is as shown in figure. The loop is pulled with a constant velocity of \(25\text{ cm/s}\) till it goes out of the field.
(a) What will be the direction of the induced current in the loop as it goes out of the field ? For how long would the current in the loop persist ?
(b) Plot graphs showing the variation of magnetic flux and magnitude of induced emf as a function of time.
Show Hint
Whenever a closed loop moves through a localized uniform magnetic field of width \(L\), the time taken to enter or leave depends solely on the size of the loop itself (\(\Delta t = \text{side}/v\)), whereas the duration of zero induction inside depends on the gap width (\(t_{\text{flat}} = (L - \text{side})/v\)). This structural intuition makes sketching verification values instantly straightforward!
