What is the change in kinetic energy of the proton?

AI Thread Summary
The discussion centers on calculating the change in kinetic energy of a proton moving through an electric field. The user initially applied the formula KE = qE/d incorrectly by squaring the distance, leading to an erroneous result. The correct approach does not involve squaring the distance, which is a common mistake in such calculations. The user acknowledges the error and expresses frustration over the math mistake that affected their test score. Accurate application of the formula is crucial for determining the correct kinetic energy change.
Dx
A proton moves .1m along hte direction of an electric field of magnitude 3V/m. what iss the change in kinetic energy of the proton?

I have KE = qE/d...1.6x10^-27 * 3V/m /(.1^2)= 4.8x 10^-25 but got it wrong on the test.
What did i do wrong?
Dx
 
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Originally posted by Dx
A proton moves .1m along hte direction of an electric field of magnitude 3V/m. what iss the change in kinetic energy of the proton?

I have KE = qE/d...

Note: In the formula, distance is not squared, which is correct.

1.6x10^-27 * 3V/m /(.1^2)= 4.8x 10^-25 but got it wrong on the test.
What did i do wrong?

You squared the distance, which is incorrect.
 
Ok!

Darn it! I missed that on my test, stupid math mistakes gets me all the time. Thanks Tom!
Dx :wink:
 

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