Download Cathode Ray Experiment

JJ Thompson’s Cathode Ray
Experiment
The Mathematical Concept
The Physical Basics
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To understand some electrical and magnetic concepts.
This includes the concept of Forces in this regions.
The Definition of Electric Field is the force experienced
by a unit charge kept in that field
Where F is the force applied and e is the charge on the
particle. E is the Electric Field Intensity
The Physical Basics
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The Definition of Magnetic Field Intensity is the Force
experienced by a unit charge moving in the field with unit
velocity
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Where F is the Magnetic Force experienced by the
charge, e is the charge on the particle, v is the component
of velocity perpendicular to the Magnetic Field Intensity. B
is the Magnetic Field Intensity.
The Direction of the force can be found with Right Hand
Rule
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What will Happen?
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The Forces will act in the y-direction. Fe will act in the
upward direction and Fm will act in the downward
direction
Therefore For Straight Travel i.e. No Deflection, Fm = Fe
From here
Now Magnetic Field is switched off..
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Therefore only Electric Field will act and thus the
electron will move towards the positive plate
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Here
Now
Also
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Thus we have
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We have y=s and x=l.