Work Done on A Proton in an Electric Field

Thread starter physicslady123
Start date Mar 28, 2021
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Electric Electric field Field Proton Work Work done

AI Thread Summary

The equation for work done on a proton in an electric field is given as W = -qEd, resulting in a calculation of -2.76 x 10^-18 J. The confusion arises regarding why the work is reported as positive, despite the proton moving in the direction of the electric field. The key point is that the work done by the electric field is considered positive, as it indicates energy supplied to the proton. The negative sign in the equation reflects the work done against the field when considering the proton's charge. Ultimately, the positive value represents the energy gained by the proton from the electric field.

Mar 28, 2021

physicslady123

Homework Statement: Calculate the work done in moving a proton 0.75 m in the same direction as the electric field
with a strength of 23 N/C

Relevant Equations: W=-qEd

W=-qEd
=-(1.6*10^-19)(23)(0.75)
= -2.76*10^-18 J

However, the answer is 2.76*10^-18 J. Why is the word done positive and not negative? Since it's traveling in the same direction as the electric field, shouldn't it be negative work?

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Mar 28, 2021

Gordianus

It seems to me the result quotes the work done by the field

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