Answer;
= 3.86 × 10^8 Meters
Explanation;
-The distance between the Earth and the moon is 386000 km
But; 1 km = 1000 m
Therefore; 386000 km will be equivalent to;
= 386000 × 1000
= 386000000 m
= 3.86 × 10^8 meters
It makes calculations with very large and small numbers easier.
Scientific notation is a system used in order to It makes calculations with very large and small numbers easier. It is useful as it allows very large number that would take a lot of space to write otherwise, and it allows them to be calculated easier.
for example is a incredible large number, but written in this form is immediately understandable and useful for calculation.
Answer:
The net Electric field at the mid point is 289.19 N/C
Given:
Q = + 71 nC = 
Q' = + 42 nC = 
Separation distance, d = 1.9 m
Solution:
To find the magnitude of electric field at the mid point,
Electric field at the mid-point due to charge Q is given by:



Now,
Electric field at the mid-point due to charge Q' is given by:



Now,
The net Electric field is given by:

