Advertisements
Advertisements
Question
Each of the capacitors shown in figure has a capacitance of 2 µF. find the equivalent capacitance of the assembly between the points A and B. Suppose, a battery of emf 60 volts is connected between A and B. Find the potential difference appearing on the individual capacitors.

Advertisements
Solution
There are three rows of capacitors connected in parallel in the given system. In each row, three capacitors of capacitance 2 μF are connected in series.
For each row, the equivalent capacitance is given by
`1/C_r = 1/2 + 1/2 + 1/2`
`⇒ C_r = 2/3 "uF"`
As three rows are connected in parallel, their equivalent capacitance is given by
`C_(eq) = C_r + C_r + C_r = 2/3 + 2/3 + 2/3 = 2 "uF"`
The voltage across each row is the same and is equal to 60 V.
As all capacitors have the same capacitance in each row, the potential difference across their plates is the same.
∴ Potential difference across each capacitor = 20 V
APPEARS IN
RELATED QUESTIONS
A bulb is connected in series with a variable capacitor and an AC source as shown. What happens to the brightness of the bulb when the key is plugged in and capacitance of the capacitor is gradually reduced?

A capacitor of capacitance C is charged fully by connecting it to a battery of emf E. It is then disconnected from the battery. If the separation between the plates of the capacitor is now doubled, how will the following change?
(i) charge stored by the capacitor.
(ii) Field strength between the plates.
(iii) Energy stored by the capacitor.
Justify your answer in each case.
A parallel plate capacitor of capacitance C is charged to a potential V. It is then connected to another uncharged capacitor having the same capacitance. Find out the ratio of the energy stored in the combined system to that stored initially in the single capacitor.
As `C = (1/V) Q` , can you say that the capacitance C is proportional to the charge Q?
When 1⋅0 × 1012 electrons are transferred from one conductor to another, a potential difference of 10 V appears between the conductors. Calculate the capacitance of the two-conductor system.
A capacitor is made of a flat plate of area A and a second plate having a stair-like structure as shown in figure . The width of each stair is a and the height is b. Find the capacitance of the assembly.

Convince yourself that parts (a), (b) and (c) figure are identical. Find the capacitance between the points A and B of the assembly.



Find the equivalent capacitance of the infinite ladder shown in figure between the points A and B.

A capacitor is formed by two square metal-plates of edge a, separated by a distance d. Dielectrics of dielectric constant K1 and K2 are filled in the gap as shown in figure . Find the capacitance.

An air-filled parallel-plate capacitor is to be constructed which can store 12 µC of charge when operated at 1200 V. What can be the minimum plate area of the capacitor? The dielectric strength of air is `3 xx 10^6 "Vm"^-1`
Three capacitors C1 = 3μF, C2 = 6μF, and C3 = 10μF are connected to a 50 V battery as shown in Figure below:

Calculate:
(i) The equivalent capacitance of the circuit between points A and B.
(ii) The charge on C1.
Dielectric constant for a metal is ______.
Consider two conducting spheres of radii R1 and R2 with R1 > R2. If the two are at the same potential, the larger sphere has more charge than the smaller sphere. State whether the charge density of the smaller sphere is more or less than that of the larger one.
The displacement current of 4.425 µA is developed in the space between the plates of the parallel plate capacitor when voltage is changing at a rate of 106 Vs-1. The area of each plate of the capacitor is 40 cm2. The distance between each plate of the capacitor is x × 10-3 m. The value of x is ______.
(Permittivity of free space, ε0 = 8.85 × 10-12C2N-1m-2).
Which expression gives the capacitance of a capacitor?
Which set lists the factors on which capacitance depends?
What is the practical purpose of a series combination of capacitors?
In a parallel combination, which quantity is the same across each capacitor?
