OCR B (Advancing Physics) - Section C

It's really bad. They say they'll ask you to know only one of 'diffraction, standing waves or interference', but then on some of the papers they explicitly ask for a diffraction effect, or a standing wave example. I have already done the sensing paper, but I used the same as you for imaging and signalling, and used a strain gauge for sensor (stretches when strained, resistance increases). For my other ones I am doing ultrasound to detect a shoal of fish, photoelectric effect, and youngs double slits (seems I am doing the same as you, then).

Reply 2

OP

ljfrugn

It's really bad. They say they'll ask you to know only one of 'diffraction, standing waves or interference', but then on some of the papers they explicitly ask for a diffraction effect, or a standing wave example. I have already done the sensing paper, but I used the same as you for imaging and signalling, and used a strain gauge for sensor (stretches when strained, resistance increases). For my other ones I am doing ultrasound to detect a shoal of fish, photoelectric effect, and youngs double slits (seems I am doing the same as you, then).

You've already done the Advancing Physics paper?

I'm looking at the UP paper from January and one of its section Cs is a standing wave example. I didn't even realise that it was in the section C-type bit of the syllabus. Looks like I have a lot more to learn before Friday than I'd thought...

For signalling, you sometimes get questions about speed of the signal and estimating the distance between the transmitter and receiver or something. How do you do this for fax?

Reply 3

OP

Oh, and does anyone HAVE a good example for diffraction and standing waves? I seem to recall a teacher saying that you can use a light source through a single slit, as used in the Young's double slit set up before lasers, as an example of diffraction, but there must be a better one...

Reply 4

Section C - Imaging Application.doc28.2KB

I've only done the sensing paper, i'm doing Understanding Processes next Fri. For standing waves you can just do a guitar string on a rigid metal frame with a sig. gen. attached to the end (i think), and for diffraction do young's slits. The speed of the signal for fax is just the speed of light (3x10^8 m/s), and for the distance I'd assume it's just the distance between the sender and the recepient.

See attachments, theyre some notes I put together whilst revising in jan, may help.

Section C - Imaging Exam Example.doc33.8KB

Section C - Sensor Application.doc35.3KB

Section C - Signal Transmission Application.doc35.3KB

Reply 5

OP

Thanks! Have some rep.

Yaaaaay! Thank you.

For superposition can you not talk about a CD drive and the destructive superposition in their that is necesary for CD's to work. pg 63 advancing physics.
Also for sensors a good one is potential didvider in car fuel guage: pg 42 advancing physics.

Reply 8

OP

chickensquirrel

For superposition can you not talk about a CD drive and the destructive superposition in their that is necesary for CD's to work. pg 63 advancing physics.
Also for sensors a good one is potential didvider in car fuel guage: pg 42 advancing physics.

Hmm, I think I find the Young's slits easier. It's mainly diffraction and standing waves I want examples for... so, Young's slits again and Kundt's cork dust tube?

Reply 9

stevesmith100

x rays is a good imaging one, and doppler imaging of heart for ultrasound.

Reply 10

Jonah

i went through the past papers last year and there were like 4 topics per paper and they were in a pattern.... it worked 4 me :biggrin:

Reply 11

What two Section C's do you think will come up in Understanding Processes this year?

Reply 12

Rixter182

We had a really bad teacher last year who quit school a month or so before our exam. Luckily our head of physics stepped in to "finish the course" and realised we hadn't done half of what we needed to do. To cut a long story short, our head of physics is one of the chief examiners for the A2 paper (knows alot about the AS paper and its examiners), so we ended up with a crash course on Understanding Processes.

For section C, he told us to learn these examples:-

-Super Position: Young's "two-slits" experiment
-Quantum Phenomenon: Ultra-violet Catastrophe (google it to get extra info)
-Measuring distance of a remote object: Firing pulses of coded radio waves at a planet, then listen out for the reflected code
-Measuring acceleration: Trolley with mass attached. Smooth pulley, surface and light inextensible string. release from rest. use SUVAT equations.

Most of you probably have all your section C stuff written up and ready to use, but thoguht there's a chance it may be useful for someone out there. Like I said it's from a reliable source! :smile:

Reply 13

Magician

ljfrugn

It's really bad.

noway! Section C is the easiest to prepare for. You can definitely score max marks on that.

Reply 14

OP

What are people learning for standing waves then? I've found the following for Kundt's tube experiment, but surely more detail would be needed:

· A metal base is placed at one end of a glass tube, with a loudspeaker connected to a signal generator at the other.
· A fine layer of cork dust or lycopodium powder is spread uniformly in the tube
· The frequency of the signal generator is adjusted until a standing wave is formed
· Heaps of dust form at the nodes, and clear areas at the antinodes
· The wavelength is 2 x distance between nodes
· The speed of sound can be found using v=fλ

Anyone got anything?

Reply 15

Magician

dinkymints

What are people learning for standing waves then? I've found the following for Kundt's tube experiment, but surely more detail would be needed:

· A metal base is placed at one end of a glass tube, with a loudspeaker connected to a signal generator at the other.
· A fine layer of cork dust or lycopodium powder is spread uniformly in the tube
· The frequency of the signal generator is adjusted until a standing wave is formed
· Heaps of dust form at the nodes, and clear areas at the antinodes
· The wavelength is 2 x distance between nodes
· The speed of sound can be found using v=fλ

Anyone got anything?

Last year, I did it on standing waves on a string. Basically, a frequency generator and a node at the other end is all you need...--> at different freq, standing waves are formed. There are some fancy formulae to go with it to.

Reply 16

Revenged

Mathemagician

Last year, I did it on standing waves on a string. Basically, a frequency generator and a node at the other end is all you need...--> at different freq, standing waves are formed. There are some fancy formulae to go with it to.

lol, i feel sorry for you lot!

A2 is a joke so don't worry.

Firstly, there's nothing to learn for it and no section C!

Plus there's no proper synopic paper you get this pink booklet telling you what you need to revise.

So if any of you are looking for an easy A next year i'd recomment carrying it on - providing you can last another year of physics! Which i know is a challenge, but is a real piece of p***!

Reply 17

Magician

Revenged

lol, i feel sorry for you lot!

A2 is a joke so don't worry.

Firstly, there's nothing to learn for it and no section C!

Plus there's no proper synopic paper you get this pink booklet telling you what you need to revise.

So if any of you are looking for an easy A next year i'd recomment carrying it on - providing you can last another year of physics! Which i know is a challenge, but is a real piece of p***!

ohh..the synoptic... Isnt it really difficult?

Reply 18

SunGod87

7

I wish I got a pink booklet telling me what to revise. The one I had only has information on a topic we will be questioned on for PART of the paper :tongue:

Reply 19