Magnet Magic

This logic puzzle was published in Martin Gardner's column in the Scientific American. You are in a room with no metal objects except for two iron rods. Only one of them is a magnet. How can you identify which one is a magnet?

Easy Math Editor

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Remember to wrap math in `$` ... `$` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$

Comments

The magnetic rod when suspended will point in north-south direction. Or you can also hold one end of one rod and see if its attracted to the centre of the other rod. Magnet will have least attraction at its centre.

Rajorshi Chaudhuri - 6 years, 5 months ago

YEAH..TRY MY OTHER LOGICAL PUZZLES TOO

vishwathiga jayasankar - 6 years, 5 months ago

Arrange the rods in shape of 'T' Let us say 'I' as rod 1 and the other as rod 2. Now move the rod 1 away from 2 in a st. line in which it is present. If rod 2 comes along with it then rod 1 is magnet.If not then rod 2 is magnet.

vempati shriram - 6 years, 5 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$