Given charge of uniform density. What is the electrical potential @?

AI Thread Summary
The problem involves calculating the electrical potential at the center of a circle with a uniform charge density of 4.50 nC/m. The correct formula for electric potential is V = kQ/r, where k is the Coulomb's constant. Initially, the user miscalculated by treating the charge density incorrectly, leading to an incorrect potential of 40.455V. The total charge was clarified as 4.50 nC/m multiplied by the circumference of the circle, resulting in a final potential of approximately 254V. The discussion highlights the importance of correctly interpreting charge density when calculating electric potential.
RedLego
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Homework Statement


Charge of uniform density 4.50nC/m is distributed along the circle of radius R. What is the electrical potential (relative to zero at infinity) at the centre of the circle?

Answer: 254V

Homework Equations


electric potential: V=kQ/r

The Attempt at a Solution


Because the charge of uniform density is 4.50 x 10^-9 C/m
I would assumed that would equal to Q/r, and all I need to do is multiply it by k, 8.99 x 10^9Nm^2/c^2.

V= (8.99 x 10^9)(4.50 x 10^-9) = 40.455V

Of course this is incorrect, tried searching it up on google, but failed. :(
 
Physics news on Phys.org
If it's 4.50nC/m, what's the total charge, Q?
 
OHH! haha thanks i got it now :)

4.50nC/m * 2pi * k = 254.5V
 

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