Answer:
r = 0.338 meters
Explanation:
Q = Source charge
q = Test charge
5μC= 5*10^-6 C
Start with the electric field equation:
[tex]E = \frac{F}{q}[/tex]
and Coulombs law
[tex]F=\frac{k|Qq|}{r^2}[/tex]
Combining these functions we get:
[tex]E=\frac{k|Q|}{r^2}[/tex]
As you can see the test charge cancels so we do not need the value of it.
Plug in your numbers:
[tex]3.93*10^5=\frac{(8.99*10^9)(5*10^-^6)}{r^2}[/tex]
solve for r
[tex]r=\sqrt{\frac{(8.99*10^9)(5*10^-^6)}{(3.93*10^5)} }[/tex]
[tex]r= 0.338 meters[/tex]
