Solving for Speed: Average Net Force & Mass

AI Thread Summary
To find the average speed of electrons impacting a TV tube, the average net force exerted by the electrons is given as 0.9 x 10^-7 N. The number of electrons per second is approximately 1.0 x 10^15, and each electron has a mass of 9.1 x 10^-31 kg. Using the formulas Favg = p/t and p = mv, one can relate force to momentum and time. By rearranging these equations, the average speed can be calculated by determining the total momentum imparted by the electrons over time. This problem requires applying the principles of physics to derive the unknown speed from the provided values.
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1. A beam consisting of around 1.0 1015 electrons per second, each of mass 9.1 10-31 kg, paints pictures on the face of a TV tube. Assuming that the electrons are absorbed by the screen and exert an average net force on it of 0.9 10-7 N, what is their average speed at impact?



2. Favg = p/t and p=mv



3. These are the two formulas given, but I'm not sure how to solve for speed
 
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Try starting the problem, and writing down your thought process.

Write and sketch about what you already know from what the problem tells you - then see if you can use that to work out what you don't yet know.
 

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