Help please A Cathode ray tube, or CRT, is diagrammed to the right. This device
ID: 2255716 • Letter: H
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Help please
A Cathode ray tube, or CRT, is diagrammed to the right. This device (which is used in many antiquated televisions) works by accelerating electrons emitted by a filament through a long (relative to an electrons) straight chamber, diagrammed as region 1 in the figure. Once the electron is accelerated, it enters a region of space (depicted as region 2 in the figure) where its path is bent as it speeds towards a phosphorescent screen. Depending on how much energy the electron has, the phosphors light up a certain color (red, blue, or green). Each electron striking the screen makes up a pixel. Explain in your own words referencing the electric and magnetic Held in each region, how the electron is made to travel the path shown in the figure (assume that in region 2, the speed of the electron is constant). In each region, you should discuss the direction (or lack thereof, in the case that the magnitude is zero) of the magnetic and the electric field REMEMBER, AN ELECTRON IS NEGATIVELY CHARGED!Explanation / Answer
F=q(V x B)
where F is Lorentz force
V is velocity of electron and B is magnetic field acting in the region
Due to the electric field the electron is made to travel towards the secreen and electric field direction is opposite to the velocity of electron because it is negatively charged.
V is known + x direction
For a lorentz force on positive y axis The magnetic field is to be into the plane of paper
For a lorentz force on negative y axis the magnetic field is outwards the plane of paper
So the magnetic field is varied along the space inside so as to give the lorentz force on the electron to make it strike at various position we require
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