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Grade upto college level Mechanics

Why doesn't the electron in the beam from an electron gun fall as much because of gravity as a water molecule in the stream from a hose? Assume horizontal motion initially in each case.

Profile image of Shane Macguire
11 Years agoGrade upto college level
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1 Answer

Profile image of Deepak Patra
11 Years ago
The mass of electron is 9.1 x 10-31 kg, therefore the magnitude of gravitational force acting on electron is significantly smaller. Also, the electron fired from the electron gun moves nearly at the speed of light, and can therefore make to its destination on the other end with in fractions of a second.
The magnitude of gravitational force is so small that it is unable to produce significant curvature in the path of electron. It is important to realize that the gravitational force provides centripetal to the moving electron, and the curvature of the electron depends on the magnitude of this force.