Solving Physics Problem 4: 24840 N/C?

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I want to know Problem 4


So P = UAC

(4.6*10^-6)(2)(3*10^8) = 2760 Watt

Then i know

P =U/T

2760 = X/ 9

X = 24840 N/C?
 
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Your calculation seems fine to me. The answer is just the energy is joules not N/C.
 
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