In the air over a particular region at an altitude of 219 m above the ground, the electric field is 141 n/c directed downward. at 319 m above the ground, the electric field is 103 n/c downward. what is the average volume charge density in the layer of air between these two elevations? (include appropriate sign in the answer).

Explanation:

Given that

219 m above the ground, the electric field is 141 N/C directed downward.

At 319 m above the ground, the electric field is 103 N/C downward.

If filed is going in to the region then it taken as negative and If filed is going out to the region then it taken as positive.

So net flux = 114 A - 103 A

 Net flux= 11 A

Now from Gauss law

q= 11 A ε

The average volume charge density(q') is the ratio of charge to the volume.

Volume = A .h

h= 319 - 219

h= 100 m

So the charge per volume is

current and voltage can both be different in different parts of a circuit so it matters where you place the ammeter and voltmete