The speed of a electron that is accelerated from rest through an electric potential difference of 120 V is 
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How to calculate the speed of the electron?</h3>
We know, that the energy of the system is always conserved.
Using the Law of Conservation of energy,
U=0
Here, K is the kinetic energy and U is the potential energy.
Now, substituting the formula of U and K, we get:
=0------(1)
Here,
m is the mass of the electron
v is the speed of the electron
q is the charge on the electron
V is the potential difference
Let
and
represent the final and initial speed.
Here,
=0
Solving for
, we get:


=6.49
m/s
To learn more about the conservation of energy, refer to:
brainly.com/question/2137260
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