Uncertainty principle and tv picture tube

AI Thread Summary
The discussion revolves around calculating the uncertainty in the position of electrons striking a TV screen after passing through an aperture. The key concept is that the uncertainty in position, Δy, leads to an uncertainty in momentum according to Heisenberg's uncertainty principle. Participants are encouraged to use Planck's constant, the mass of an electron, and the charge of an electron in their calculations. The uncertainty in momentum is linked to the distance x from the aperture to the screen. Understanding these relationships is essential for solving the problem effectively.
matpo39
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hey, I am really confused with this problem, i have tried to solve it for a while now but i can't seem to get it, i really don't even know where to start with it.

In a TV picture tube the accelerating voltage is V, and the electron beam passes through an aperture with a diameter of Delta_y and hits a screen which is a distance of x away.

What is the uncertainty in position of the point where the electrons strike the screen?
Use h for Planck's constant, m_e for the mass of an electron, and e for the magnitude of the charge on an electron.

any help would be great.
 
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The idea is that the uncertainty in the position of the particle after it passes the aperture is \Delta y, which, if it is small enough, leads to an uncertainty in the momentum of the particle.

Use Heisenberg to find the order of this uncertainty in momentum.
 
when i find the uncertainty in the momentum that will be the x component of the momentum since it is a distance x away from the tv?
 

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