What Causes the Shadow in a Cup?

[matthew77ask]

Hello,

I need help... I have been assigned in physics to look at the shadow in the cup and mysearch shows me caustic curves...

I have very little information on this to do a 4 page report on...

can someone please point me to some sites, url etc on this...

many thanks

 

[tiny-tim]

Hi matthew!

I suggest you start with wikipedia …
http://en.wikipedia.org/wiki/Caustic_(mathematics)
http://en.wikipedia.org/wiki/Cusp_(singularity)
http://en.wikipedia.org/wiki/Caustic_(optics)