You are Here: Home >< Physics

# Tracks in chambers (PHY6) watch

1. How do you tell what direction a track will go? They always say if the magnetic field goes into/out ofthe plane of the paper which way will the track go if the particle is positive/negative, how do you tell this. Also how does momentum effect the tracks?
2. direction of a track is random
3. the magnetic field causes the direction of the track not to be random, ment to say in spark and drift chambers. Think they r random in cloud and buble chambers. I really hope we dont get a question on chambers coz i really dont like them!
4. If theres a magnetic field into/out of the plane of the paper, then you use flemings left hand rule.

You know the direction of the field, and the current is the direction a positive charge moves in (conventional current, if a negative charged particle moves left, the current is right). Using flemings left hand rule you can now see which way the track is bent.

The faster a particle goes (the higher the momentum), the less the particle ionises, and hence the thinner the track. Slower particles ionize more and thus give give thicker tracks.

Particles going slower also move in a curve of smaller radius ( tighter circle) than faster particles.
5. getting so confused, which way should my thumb b pointing?
6. Thumb is force (So if the thumb points up then the particle will be bent upwards, this usualy points towards the center of a circle).

First finger is the direction of the field (the direction a single north pole would move).

2nd finger is the directionary current direction.
7. Here is one thats annoying me:

The photo shows particles tracks.... A=>B and c=>d are negative and c=>e is positive, if there were a strong magnetic field acting down perpendicular to the plan of the photograph, what would the shape of the tracks be mark scheme says the answer is that A to b and C to d curves upwards and then downwards in arc c to e curves in the opposite direction.

The photo is something like this

==== <

Im assuming it would curve back again because it's slowly decaying yes?
8. first one would be a semi circle going UP. the one going diagonally upwards would do the same except curved (semi circle again). the last one would curve downwards (semi circle)

___--->--___ (first)

___->--___ (one originally going diagonally up)

----___-->- (one goind diagonally down originally)
9. Yo! invictus, some guys don't get half of what u just did, and the question, how did u analyse that little diagram. Pls, explain further. Thanks
10. for flemings left hand rule remember FBI...thumb=F...etc
11. I think that is wrong. the magnetic field goes into the paper, the current goes in the opposite direction of the movement of A to B because A to B is negative, use the left hand rule.. first finger points into the page, second finger points backwards from B to A and the thumb points down. So A to B will curve down

From B to C there is no mark and therefore a neutral particle, so it will travel in a straight line. and CD will also curve clockwise and CE will curve anticlockwise as its positive, so the two will set off at an angle but then curve towards each other.

Thats what I said
12. arc clockwise of A to B

arc anti-clockwise of C to E
13. yep I agree with that, I think thats what the other people meant I just dont know why from A to B the particle starts travelling at an angle above horizontal beause in the picture they gave it just starts travelling across. I drew:

__.....
....\...
........._
....|......\
.....\_....|

kinda like that
14. guys guys is THIS edexcel or OCR?
15. Well its definetly in EDEXCEL, but i dont know the OCR sylabus

### 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 26, 2005
The home of Results and Clearing

### 2,240

people online now

### 1,567,000

students helped last year
Today on TSR

### University open days

1. Keele University
Sun, 19 Aug '18
2. University of Melbourne
Sun, 19 Aug '18
3. Sheffield Hallam University
Tue, 21 Aug '18
Poll

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE