I'm homeschooled so it's not always simple to find explanations for things I don't get.
I've been struggling with 'Light' in physics for a week now (Edexcel P1, P3). The book I'm using doesn't clearly outline how to calculate refractive index and speed from refractive index. I'll try to break this down into questions:
1. How do you calculate speed from refractive index?
2. How do you calculate refractive index in the first place?
3. Probably the dumbest question but in formulae such as [sin], what does 'sin' mean? I know it's to do with angles but it never came up in math or physics lessons while I was in school - part of the reason I left was because they were understaffed and we were very behind in various subjects.
Any help would be much appreciated.