Question

Assume we have a parallel-plate capacitor.

(1) If we increase the distance between the plates, what will happen to its capacity?

(2) If we increase the surface area of the plates, what will happen to its capacity?

(Hint: How do you calculate the capacity of a capacitor?)

Answer 1

a) C =Q/∆V =εA/d(Parallel plate capacitor)

As we can see from the above formula that Capacitance mainly depends on A and D . The capacitance increases linearly with the area(A) fro the given potential differences bigger the plate more the charge and also we can see capacitance is inversely proportional to distance(d).

If we increase the distance between parallel plates with new distance twice of the original distance 2d in which C becomes half of the previous capacitance and at a constant flow with increase in C will decrease the charge Q that conductors can hold.

b) C =Q/∆V =εA/d(Parallel plate capacitor)

From the above formulas we can conclude one thing that C is directly proportional to  Area(A) where when the surface area is increased then C will also increases linearly. A larger capacitance will hold bigger charge at same voltage where Doubling the area will doubling the capacitance capacity.