Verifying an Electron's Final Speed After Releasing from Rest

AI Thread Summary
The problem involves calculating the final speed of an electron released from rest between two positive point charges. Using the conservation of energy principle, the equation Ek(f) + U(f) = Ek(i) + U(i) was applied to find the final speed when the electron is 10.0 cm from charge 1. The calculated final speed was 7.53 x 10^6 m/s. Despite initial concerns about the high speed, the answer was confirmed to be correct. The discussion highlights the importance of verifying calculations in physics problems.
rowkem
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Homework Statement



Two stationary positive point charges, charge 1 of magnitude 3.45 nC and charge 2 of magnitude 1.85 nC, are separated by a distance of 50.0 cm. An electron is released from rest at the point midway between the two charges, and it moves along the line connecting the two charges.

What is the speed v(final) of the electron when it is 10.0 cm from charge 1?

Homework Equations



Ek= (mv^2)/2
U= (k(q1q2))/r

The Attempt at a Solution

I used the following equation:

Ek(f)+U(f) = Ek(i)+U(i)

(mv(f)^2)/2 + (k(q1q2))/r = (mv(i)^2)/2 + (k(q1q2))/r

(9.1x10^-31)(vf)^2)/2 + (((9x10^9)(3.45nC)(-1.6x10^-19))/0.10m) + (9x10^9)(1.85nC)(-1.6x10^-19))/0.40m) = (((9x10^9)(3.45nC)(-1.6x10^-19))/0.25m) + (9x10^9)(1.85nC)(-1.6x10^-19))/0.25m)

v(f) = 7.53 x 10^6 m/s

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So that's my answer. I lose marks if I submit an incorrect answer. That said, I just want to double check my answer before submitting it. A simple yes or no will suffice. Thanks in advance.

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That seems unreasonably high. Maybe I'm just ignorant but, guess we'll see.
 
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Took a stab at it. Was correct. Thanks everyone.
 
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