The potential at the surface of a 19 cm-radius sphere is 5.0 kV. What is the charge on the sphere, assuming it's distributed in a spherically symmetric way? (Answer to two significant figures)
So far, I've used, Q = r*V/k
where r = 19, V=5, k = 8.988*10^9
So that Q = 19 * 5/8.988*10^9
= 10.1 nC = 1.01e-8 C
But when I input that, it turns out wrong. I'm guessing that my conversions went wrong, or something like that.
So far, I've used, Q = r*V/k
where r = 19, V=5, k = 8.988*10^9
So that Q = 19 * 5/8.988*10^9
= 10.1 nC = 1.01e-8 C
But when I input that, it turns out wrong. I'm guessing that my conversions went wrong, or something like that.
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V = k Q/R where k is coulombs constant.
(= 8.987 * 10^9 N m^2 / C^{2} according to wikipedia)
so Q = VR/k
substitute and evaluate
R= 0.19, V= 5000
So Q = 5000 * 0.19 /(8.987 * 10^9) = 1.06 * 10 -7 C
One problem you had was failing to convert the values to SI
5 Kv is equivalent to 5000 V
and 19 cm is equivalent to 0.19 m
I can see no other problems with your approach or calculations.
(= 8.987 * 10^9 N m^2 / C^{2} according to wikipedia)
so Q = VR/k
substitute and evaluate
R= 0.19, V= 5000
So Q = 5000 * 0.19 /(8.987 * 10^9) = 1.06 * 10 -7 C
One problem you had was failing to convert the values to SI
5 Kv is equivalent to 5000 V
and 19 cm is equivalent to 0.19 m
I can see no other problems with your approach or calculations.