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Question
Which of the following substance contracts on heating?
Options
Lukewarm water
Ice
Iron
Mercury
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Solution
Ice
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Your teacher has shown you the following activity.

Activity: Teacher has wound a long insulated piece of wire around an iron nail in the form of a coil. Free ends of the wire are connected to a cell through a switch as shown in the following figure. The current is switched on and some pins are placed near the ends of the nail.
Write down any three questions that come to your mind about this activity.
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| A | Nail | 3.0 | 3.15 |
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