Calculating Electron Velocity with 3eV Energy

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To calculate the velocity of an electron with 3 eV energy, the conversion to joules yields 4.8E-19 joules. Using the kinetic energy formula, the initial velocity is calculated to be approximately 10^6 m/s. The electric field of 10 V/cm is equivalent to 100 N/C, which is relevant for determining acceleration. After applying the kinematic equation for the final velocity, a result of 1.03E6 m/s is obtained, indicating a small change in velocity. The calculations appear correct, but the minor velocity difference raises questions about the results.
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Homework Statement



Calculate the velocity of an electron with 3 eV energy. This electron is accelerated by a constant field of 10 V/cm (parallel to the electron velocity) for 0.1 cm. What is the new electron velocity?

My other problem is the unit for the electric field . it bothers me: V/cm usually it is N/C

Homework Equations


.5*m*v^2

Please can i have some suggestions?

The Attempt at a Solution


3eV=3 x 1.6E-19=4.8E-19 joules=1/2 mv^2, so v^2=4.8E-19/4.5E-31=1E12
so v=10^6 metres/sec.
 
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You should be aware of the fact that 1 V/m = 1 N/C. So 1 V/cm is how many N/C?
 
100 N/C
thank i forgot all those units!

to find the final speed, i use the formula (Vfinal)^2-(Vinitial)^2=2a*(0.1 e-2)
when i did I found Vfinal =1.03 e6 m/s

the velocity difference i think is very small , it seems not right. did i do the question corretly?
thank you
 
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