today we're performing the smiling bill experiment. it's one of my favorites and it's a lot of

fun firstly you're going to need a £10 note or

any note with a face but do make sure that the face is facing forwards

you'll see here that on this £10 note we have the face of the queen of england

what you need to do first is fold the £10 note over so that there is a crease that runs

down the center of her right eye then fold the note again in the same direction

to form a crease down the center of her left eye

then very carefully push those two creases together to form a crease running in the opposite

direction if you do it right she'll look a little bit

like a cyclops once you've done that straighten the note

out again but make sure there is still a bend in the paper and then slowly tilt the piece

of paper backwards and forwards you'll see that the queen starts to frown

or smile depending on which way you tilt the paper

but how does this work well it's very simple it's because of the

fold in the paper it slightly changes the angle at which you're

looking at that section of the picture we can try this experiment again with a $20

bill use the same technique

place a crease through each of the eyes and then a third crease running between the

two if we straighten out the bill and then tilt

it you'll see that jackson becomes very happy and then very sad

and there we have it that is the smiling bill experiment

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