# physics G485 OCR - long style question answers

I got the resources from another source but shortened it into managable chunks

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• Created by: Jessica
• Created on: 11-06-13 16:38
A mass spectrometer is used to...
Identify particles once they have been ionised
1 of 15
What is controlled in order to measure mass
Movement in electric and magnetic feilds
2 of 15
The sample is first...
Vapourised and ionised
3 of 15
Then a fine beam of...
positively charged ions are sent into a velocity slector
4 of 15
It has a magnetic flux density meaning...
only particles with a certain velocity will be able to get through the small slit
5 of 15
The beam enters...
A second magnetic field and is deflected. - the radius of deflection can be used to measure mass
6 of 15
equation used to measure the mass - from a mass spectrometer
m= BQr / v - the horizontal velocity stays the same
7 of 15
Uses of capacitors
*Flash photography *Back-up power supply on a computer *Nuclear fusion
8 of 15
Production of X-rays - electrons are
Removed from filament by heating
9 of 15
Work is done on electrons by
accelerating it through an electric field (PD)
10 of 15
the electrons are directed towards
A metal target (Mo) causing the electrons to be excited to higher energy levels
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When the (Mo) electrons de-ecxite
x-ray photons are produced
12 of 15
Photo electric effect
low energy x-rays (
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Pair Production
x-ray photons (>1.2MeV) passes thorugh the electric field of thenucleus and produces an electron-positron pair. The positron is anihilated by another electron
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Compton Scattering (/effect)
x-rays photon (.5-5MeV) knocks an electron out of an atom, the interaction between the photon and electron is inelastic meaning the scattering photon has less energy than before so a greater wavelength.
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## Other cards in this set

### Card 2

#### Front

What is controlled in order to measure mass

#### Back

Movement in electric and magnetic feilds

### Card 3

#### Front

The sample is first...

### Card 4

#### Front

Then a fine beam of...

### Card 5

#### Front

It has a magnetic flux density meaning...