Calculating Electric Field Strength to Stop an Electron

AI Thread Summary
To calculate the electric field strength required to stop an electron moving at 3% the speed of light over a distance of 6.0 cm, the force equation F = q * E is used. The initial speed of the electron is calculated to be 9,000,000 m/s. However, the discussion highlights that the charge and mass of the electron must be considered, particularly its relativistic mass, which was not accounted for in the initial calculation. A value of 50 * 10^-6 is mentioned, but its origin and relevance are questioned. Accurate calculations require incorporating these factors to determine the correct electric field strength in N/C.
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Homework Statement



An electron moving to the right at 3% the speed of light enters a uniform electric field parallel to its direction of motion. The electron is to be brought to rest in the space of 6.0cm.
What is the strength of the field?______N/C

Homework Equations



F = q * E

The Attempt at a Solution



Speed = .03 * 3*10^8 = 9,000,000
distance = 6cm = .06m

F = .06 * 9,000,000 = 5.4*10^5 = 5.4*10^2 N/C
 
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While calculating the field you have not taken into account the charge and mass of the electron. Here you have to take the relativistic mass.
 
And that would be 50 * 10^-6 ?
 
And that would be 50 * 10^-6 ?
From where did you get this number? What is this?
 
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