A thundercloud has an electric charge of 43.2 C near the top of the cloud and -38.7 C near the bottom of the cloud. The magnitude of the electric force between these two charges is 3.95 x 106 N. What is the average separation between these charges?

Please explain.

Question

A thundercloud has an electric charge of 43.2 C near the top of the cloud and -38.7 C near the bottom of the cloud. The magnitude of the electric force between these two charges is 3.95 x 106 N. What is the average separation between these charges?

Please explain.

nincompoop · Answer

do you know the formula?

ashleyisakitty · Answer

not really.. ive studying coulombs but havent memorized the formulas within yet. F = (kq1q2)/r^2?

nincompoop · Answer

$$F _{electric}=k_c \frac{ q_1q_2 }{ r^2 }$$

ashleyisakitty · Answer

(kc=8.99×10^99N*m^2 / C^2)?

nincompoop · Answer

so in your case you have:
$$k_c=\frac{ (43.2C)(-38.7C }{ r^2 }=3.95\times10^6N$$

nincompoop · Answer

get the value of r
$$r=\sqrt{k_c \frac{ q_1q_2 }{ F _{electric} }}$$

nincompoop · Answer

ignore my = after the k_c

nincompoop · Answer

plug the values in @Ashleyisakitty and you have your answer :) 
= 1,951 m

ashleyisakitty · Answer

Awesome! Also, K=Q1Q2/D2 is forumla that works with Coulombs right?

nincompoop · Answer

tell me if you have the same

nincompoop · Answer

yes http://cnx.org/content/m42308/latest/?collection=col11406/latest

ashleyisakitty · Answer

Thanks Nin for helping out. I used the formula i listed and got the same answer. Even though formulas are just plugging in numbers theyre always a bitt confusing at first for me.