Consider a metal ring kept (supported by a cardboard) on top of a fixed solenoid carrying a current I (refer to the figure given in previous question). The centre of the ring coincides with the axis of the solenoid. If the current in the solenoid is switched off, what will happen to the ring?

Consider a metal ring kept (supported by a cardboard) on top of a fixe

1.	Consider a metal ring kept (supported by a cardboard) on top of a fixed solenoid carrying a current I (refer to the figure given in previous question). The centre of the ring coincides with the axis of the solenoid. If the current in the solenoid is switched off, what will happen to the ring?
Answer» SOLUTION :The ring will stay on the CARDBOARD but it will exert a downward force on the cardboard. As the current in the solenoid is DECREASING, then according to Lenz.s law, this decrease will be resisted and this can happen if the current in the ring is in opposite direction as in the solenoid, i.e. clockwise (as seen from the top of the ring). SINCE opposite poles are developed on sides of ring and solenoid FACING each other, the ring gets attracted towards the solenoid, in the downward direction. So, the ring exerts a downward force on the cardboard.

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Consider a metal ring kept (supported by a cardboard) on top of a fixed solenoid carrying a current I (refer to the figure given in previous question). The centre of the ring coincides with the axis of the solenoid. If the current in the solenoid is switched off, what will happen to the ring?

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