The Grade 11 Physics group has been making use of our latest piece of new equipment – a dual beam tube – to measure the charge to mass ratio (q/m) of electrons. Electrons are accelerated to a velocity of up to ten million metres per second, before being bent into a circular path by a magnetic field. By measuring the diameter of the circle and the current in the field coils, q/m can be determined. The path of two electron beams can be seen as orange lines in the tube, caused by the electrons striking neon atoms present at low pressure.
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