Coil Accelerating plates A \"cathode ray tube\" (CRT), as shown in the image at
ID: 1780479 • Letter: C
Question
Coil Accelerating plates A "cathode ray tube" (CRT), as shown in the image at right and the diagram below, is an evacuated glass tube. A current runs through a filament at the right end of the tube. When the metal filament gets very hot, electrons occasionally escape from it. These electrons can be accelerated away from the filament by applying a potential difference Avacc across the metal plates labelled A and B in the diagram. The electrons pass through a hole in plate B and enter the glass sphere. There they pass between the two horizontal metal "deflection" plates labelled C and D. A potential difference AVdef can be applied across these plates, to deflect the beam of electrons. In front of and in back of the glass sphere are two coils, through which current can be run to produce a magnetic field in the region between the deflection plates. The coils are oriented so they both produce magnetic fields into the page in this region. Coil Deflection plates P; QARA h boj out of the page Ok into the page fd 0 m zero magnitudeExplanation / Answer
ke = q deltaV
m v^2 / 2 = q deltaV
(9.109 x 10^-31) v^2 / 2 = (1.6 x10^-19) (3.1 x 10^3)
v = 3.30 x 10^7 m/s ...........Ans
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B = u0 IN R^2 / (x^2 + R^2)^(3/2)
u0= 4pi x 10^-7
I = 0.5 A
N =320 tunrs
R = 0.06 m
x = 0.03m
putting inn values,
B = 2.40 x 10^-7 T ........Ans
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E = v B = 79127.5 v/m
delta(V) = E.d = (79127.5)(8 x 10^-3 )
= 633 volt .......Ans