Answer: 1.51 km
Explanation:
<u>Coulomb's Law:</u> The electrostatic force between two charge particles Q: and Q2 is directly proportional to product of magnitude of charges and inversely proportional to square of separation distance between them.
Or, 
Where Q1 and Q2 are magnitude of two charges and r is distance between them:
<u>Given:</u>
Q1 = Charge near top of cloud = 48.8 C
Q2 = Charge near the bottom of cloud = -41.7 C
Force between charge at top and bottom of cloud (i.e. between Q: and Q2) (F) = 7.98 x 10^6N
k = 8.99 x 109Nm^2/C^2
<u>So,</u>

Therefore, the separation between the two charges (r) = 1.51 km
Answer:
Generally speaking, scientists have developed four different methods of determining the age of the earth. By using these methods, or a combination of them, the age of geological formations created by past events and even the fossilized bones of prehistoric animals can be determined.
Based on the research done by scientists, the Geologic Column, a graph that illustrates earth age, was developed. The Column, with its names for the epochs and eras of time, illustrates what scientists think was taking place in earth history. A small version of the Geologic Column is pictured at the right.
Explanation:
I hope this helps :)
The period of the pendulum doesn't determine the length of the string.
It's the other way around.
The period of the pendulum is proportional to the square root of its length.
So if you want to triple the period, you have to make the string nine times
as long as it is now.