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Question
Answer in brief:
If the difference between the radii of the two spheres of a spherical capacitor is increased, state whether the capacitance will increase or decrease.
Solution
A spherical capacitor's capacitance is `"C" = 4π ε_0 ("ab"/("b" - "a"))`
where a and b are the radii of the concentric inner and outer conducting shells. The capacitance depends only on the geometrical factors, a and b. Hence, if the difference b - a is increased, the capacitance decreases.
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