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Homework Help: Cathode ray tube

  1. Dec 9, 2004 #1
    In a Cathode Ray Tube, the deflection on the screen is 2.4cm when the accelerating voltage is 480V, and the deflecting voltage is 36V. What deflection will you see on the screen if the accelerating voltage is 960V and the deflecting voltage is 18V?
  2. jcsd
  3. Dec 9, 2004 #2
    Some hints...The deflection is proportional to the deflection voltage. But it's inversely proportional to the velocity of the electron, since a faster electron spends less time between the deflection plates than a slower one. Finally, the kinetic energy of an electron is proportional to the acceleration voltage.
  4. Dec 10, 2004 #3
  5. Dec 10, 2004 #4
    I've given you everything you need to know to solve the problem. I'm certainly not going to solve it for you!
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