Heads Up!

Posted by: on Apr 18, 2013 | No Comments

Believe it or not you can put your head through a hole in a 3 x 5 inch (7.6 x 12.7 centimetre) file card or postcard!

Adults will need to help younger children with the marking up and cutting out.

Hint: it is advised that you have a practice first with this one – note that you should be able to fit either an adult or a child’s head through the hole.

You will needpostcard

One 3 x 5 inch (7.6 x 12.7 centimetre) file card

Scissors

Instructions

1. Fold the file card in half lengthwise and make 13 partial cuts width-wise. First cut through the folded side, then turn the card around and cut toward the fold. Keep repeating the process. (Cut to within a quarter inch (half centimetre) of the edges of the card.)

2. Very carefully open the card and cut lengthwise along the fold. Do not cut the two end sections.

3. Gently stretch the card as far as it will go and put it over your head.

 

What’s Happening?

The secret to this trick comes from a branch of mathematics called topology.

It teaches that figures can be stretched without changing their area.

Have Fun!

Thanks to, and adapted from nationalgeographic.co.uk