How Does a 19kV Potential Difference Affect Electron Deflection in TVs?

AI Thread Summary
In a television set, electrons are accelerated through a potential difference of 19kV, gaining kinetic energy equal to eV, where e is the electron charge. The speed of the electrons can be determined after they exit the electric field and enter a 0.28T magnetic field. The maximum magnetic force experienced by the electrons occurs when sin(theta) equals 1. To calculate this force, use the formula F=qvB, substituting the known values for charge, speed, and magnetic field strength. Understanding the relationship between potential difference and electron acceleration is crucial for solving the problem.
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Homework Statement


In a television set, electrons are accelerated from rest through a potential difference of 19kV. The electrons then pass through a 0.28T magnetic field that deflects them to the appropriate spot on the screen. Find the magnitude of the maximum magnetic force that an electron can experience.

Homework Equations



F=qvBsin(theta)
E=-V/x

The Attempt at a Solution


I am trying to figure out where the potential difference comes into play but am not sure because E and x are not given. Any hints would be great, thanks.
 
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When the electrons are accelerated across the potential given, they gain kinetic energy =eV, where e is the charge on the electron. Using this, you can find the speed of the electron once it leaves the electric field and enters the magnetic field.

Then, the maximum magnetic force will be when sin(theta)=1. The speed you know, the magnetic field strength you know, and q=e=charge on electon. Solve for F.
 
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