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- Jan 25, 2010
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Okay so the question asks about air acting as an insulator between the thundercloud and the ground and what the effect of air is before the lightning strike...
I understand that air, acting as an insulator or a dielectric, will increase the capacitance... but why is the answer A (The air slightly reduces the potential difference between the cloud and the ground from what its value would be if air were absent)?
The teacher said: using the Q = CV formula, because Q is constant and C increases, V must decrease. Thus, choice A is the answer.
What I don't get is... Why is Q constant for this question?
I understand that air, acting as an insulator or a dielectric, will increase the capacitance... but why is the answer A (The air slightly reduces the potential difference between the cloud and the ground from what its value would be if air were absent)?
The teacher said: using the Q = CV formula, because Q is constant and C increases, V must decrease. Thus, choice A is the answer.
What I don't get is... Why is Q constant for this question?
