What is the magnitude of the force between two charges using Coulomb's law?

AI Thread Summary
The discussion focuses on calculating the force between two charges using Coulomb's law. The initial calculation incorrectly used microcoulombs and centimeters without proper unit conversion. After correcting the units to coulombs and meters, the revised calculation yields a force of 1.58 N. Participants emphasize the importance of unit consistency in physics problems. The final answer is confirmed as correct after adjustments.
yoshiba
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Homework Statement


What is the magnitude of the force a +12 µC charge exerts on a +2.7 mC charge 43 cm away?


Homework Equations


I know I have to use the equation: F=kq1q2/r^2



The Attempt at a Solution


F=(9*10^9)(12)(2.7)/(43^2)
=157706868.6

?right?
 
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yoshiba said:

The Attempt at a Solution


F=(9*10^9)(12)(2.7)/(43^2)
=157706868.6
?right?

almost, attention to the unit system you are using...
 
so i would change mC to C and cm to m...
F=(9*10^9)(2.7*10^-6)(12*10^-6)/(.43^2)
=1.58 N

is this ok?
 
Last edited:

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