What is the Maximum Magnetic Force on an Electron in a Television Set?

AI Thread Summary
Electrons in a television set are accelerated through a potential difference of 23 kV before entering a 0.29 T magnetic field. The maximum magnetic force on an electron is calculated using the formula F = BQVsin(theta), with theta set to 90 degrees for maximum force. The charge of the electron is 1.6 x 10^-19 C, and its velocity is derived from the potential difference using the equation v = sqrt(2qV/m). The calculated velocity is approximately 592,673.9 m/s, leading to a maximum magnetic force of 2.75 x 10^-14 N. The discussion highlights the importance of including all variables, particularly the potential difference, in calculations.
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Homework Statement


In a television set, electrons are accelerated from rest through a potential difference of 23 kV. The electrons then pass through a 0.29 T 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


B=F/QVSin(theta)


The Attempt at a Solution


Since I'm solving for F, i got it by itself:F=BQVSin(theta). I had theta equal to 90, because a charge experiences Fmax when perpendicular to the field. I had q=1.6x10^-19, which is the charge of an electron. I know that the potential difference is 23 kV, but i cannot figure out how to solve for V
 
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to solve for v, i tried v=(Square root)2q/m. so 2(1.6e-19)/(9.11e-31)=592673.9=v. then F=0.29*(1.6e-19)(592673.9)=2.75e-14
 
You appear to have missed a variable, that of the potential difference over which the electrons were accelerated. Apart from that your method appears quite all right.
 
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