You are Here: Home >< Physics

# AQA A 10-synoptic-refraction watch

1. does anyone know what I have to know about refraction? there seem to be a lot of questions on it in past papers, and I can't find my notes for that chapter anywhere.

I know sinΦc=n1/n2 and that is the critical angle

but how to you find angle of incidence,refraction etc, and how do you draw a ray that will totally internally reflect/refract, i know it has to have an angle greater than the critical angle but i don't know which side of the line is supposed to be greater if that makes any sence, so please HELP
2. for angles of incidence and refraction the angle in question is always about the one to the normal.

example

you see where two θ equal each other is Total Internal Reflection

look at attachment for what a Normal is. just perpendicular imaginary line. the blue thing shows its perpendicular, and the green angle is the angles that are incident and refraction θ.
Attached Images

3. i did unit 4 and unit 7 and got unit 10 left. i thought unit 4 was a bit of a disaster for me i revised using loads of past papers and thought they were all easy but then this unit 4 was nothing like them. so i'm really disappointed with that oh well i hope unit 10 makes up, and i think unit 7 went ok
4. (Original post by xelprep)
for angles of incidence and refraction the angle in question is always about the one to the normal.

example

you see where two θ equal each other is Total Internal Reflection

look at attachment for what a Normal is. just perpendicular imaginary line. the blue thing shows its perpendicular, and the green angle is the angles that are incident and refraction θ.
thanks, but say in a question where it gives you the angle of refraction as 40° and the refractive index of n1=1.5 and n2=air how do you calculate the angle of incidence?
5. (Original post by xelprep)
i did unit 4 and unit 7 and got unit 10 left. i thought unit 4 was a bit of a disaster for me i revised using loads of past papers and thought they were all easy but then this unit 4 was nothing like them. so i'm really disappointed with that oh well i hope unit 10 makes up, and i think unit 7 went ok
5 was a bit of a disaster for me as well but 9 was an even bigger disaster so i am putting all my hopes on 10 as well!
6. Hi, does anyone have the January 2005 Synoptic paper, preferably with a markscheme? If they do i would be extremely grateful if you could send it to my email: [email protected]. Thanks, ken
7. (Original post by orangazhang)
Hi, does anyone have the January 2005 Synoptic paper, preferably with a markscheme? If they do i would be extremely grateful if you could send it to my email: [email protected]. Thanks, ken
hey sorry i don't have it but if you are going to try hijack my thread, could you at least offer some pearls of wisdom about the actual topic?
thanks, but say in a question where it gives you the angle of refraction as 40° and the refractive index of n1=1.5 and n2=air how do you calculate the angle of incidence?
Ok well....

1n2=sin(i)/sin(r) Also 1n2=n2/n1

so, sin(i)/sin(r)=n2/n1

so, (i)=sin-1(n2 *sin(r))/n1

pop in your values and there you go.....

Hope that helps
Lucy x
9. http://antonine-education.co.uk/Phys..._2/topic_2.htm
Have a look there
10. Thanks everyone I have got it now role on mod10!

### Related university courses

TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

This forum is supported by:
Updated: June 24, 2005
The home of Results and Clearing

### 3,165

people online now

### 1,567,000

students helped last year
Today on TSR

### University open days

1. London Metropolitan University
Sat, 18 Aug '18
2. Edge Hill University
Sat, 18 Aug '18
3. Bournemouth University