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How to calculate the momentum of an electron ?. Measuring the radius of curvature in a magnetic field …. If electrons are moving in a magnetic field, they are forced in a circle. If they lose energy as they more they go in spirals. The Lorentz-law helps to describe this behaviour :.
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How to calculate the momentum of an electron ? Measuring the radius of curvature in a magnetic field … Dora Wagner & Miguel Vieira HST 2001
If electrons are moving in a magnetic field, they are forced in a circle. If they lose energy as they more they go in spirals Dora Wagner & Miguel Vieira HST 2001
The Lorentz-law helps to describe this behaviour : Dora Wagner & Miguel Vieira HST 2001
goes into the page ! Dora Wagner & Miguel Vieira HST 2001
The Lorentz-force is the centripetal force, which pulls the electrons to the centre : Dora Wagner & Miguel Vieira HST 2001
Look at this sketch……then click on it ! Dora Wagner & Miguel Vieira HST 2001
How do you measure the radius ? Dora Wagner & Miguel Vieira HST 2001
r = ? If we know the radius r … Dora Wagner & Miguel Vieira HST 2001
B = ? … and if we know the strength of the magnetic field B… Dora Wagner & Miguel Vieira HST 2001
… we are able to calculate the momentum : Dora Wagner & Miguel Vieira HST 2001
Try it ! What to measure, what to know Scale 1 : 6.4 For more information click here Dora Wagner & Miguel Vieira HST 2001
In Fermilab where this picture was taken, the magnetic field was : B = 3 Tesla The charge of the observed electron is : e = 1.6x10-19 Coulomb Dora Wagner & Miguel Vieira HST 2001
A photon travelled between the two marked points which was 11.5 cm in the real experiment. If you want to know more,click-me Dora Wagner & Miguel Vieira HST 2001
Can you use Pythagoras’s theorem to calculate the radius r from L and D ? BACK Dora Wagner & Miguel Vieira HST 2001