Recent content by timothy123

I'm a beginning secondary science teacher (admittedly with a biology specialism), and if I had to second guess a GCSE paper, I'd say it was simply asking why there is no refraction at A, whilst there is at B, in the diagram below: http://img151.imageshack.us/img151/3686/flowroot5110jd8.png...

Maybe if you ignore whatever is happening first on the right (assuming the light is going right->left), and imagine the light is just a 'horizontal' beam, like the one in the centre. Are they not just asking you to talk about the 'normal', as you did above?

Thanks Kurdt. A much-appreciated pointer. Does that mean that the following is true?: http://img259.imageshack.us/img259/7027/screenshot3ch4.png It was this youtube video that took me there... http://youtube.com/watch?v=OS-EnAFKWpI Seems like a great resource for basic maths tips.

[SOLVED] Radioactive decay Hi guys, this is just a basic maths incompetency. I hope someone can guide me forwards! (Slack biology student, delving into physics) I can do (a) with no problems, and thus I can probably do the latter half of (b) and (c) without issue. My stumbling point is...