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A small bar magnet is moved through a coil at constant speed from one end to the other. Which of the following series of observations will be seen on the galvanometer G attached across the coil? Three positions describe: (i) the magnet's entry, (ii) magnet is completely inside and (iii) magnet's exit.

Asked in JEE Main 4th Sept 2nd Shift 2020 · Direction of the induced current

• (1) (i) needle right (ii) needle down (iii) needle left
• (2) (i) needle at zero (ii) at zero (iii) at zero
• (3) (i) needle right (ii) needle at zero (iii) needle left
• (4) (i) needle at zero (ii) at zero (iii) needle right

Step-by-step solution

Why the other options are wrong

• (1) comes from a deflection needs a changing flux, not a stationary magnet
• (2) comes from there is certainly an emf while the magnet moves
• (4) comes from the entry and exit cannot give the same direction

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