Question
Question: Unit of capacitance is A) Coulomb B) Farad C) Henry D) Ohms...
Unit of capacitance is
A) Coulomb
B) Farad
C) Henry
D) Ohms
Solution
The unit of electric charge is coulomb and unit of potential difference is the volt, so that the capacitance is one coulomb per volt. It is named Farad, symbolized as F. The other units are μF,nF,pF.
Formula Used:
We will be using the formula of Capacitance C=VQ
Complete step by step answer:
Capacitance is defined as the ratio of the change in an electric charge in a system to the change in its potential. The SI unit of capacitance is Farad. It is represented by F.
The name of the unit came from the English physicist Michael Faraday.
Farad is defined as the ability of an object or body to store an electrical charge. It is represented ass4A2m−2kg−1.
The capacitance for a particular particle with one Coulomb charge and its potential difference of one volt is known as one farad.
The dimensional formula of capacitance is M−1L−2T4I2.
If charge Q is given to a conductor and due to its potential increases by V, then Capacitance of conductor isC=VQ where, V is the voltage, C is the capacitance, Q is the charge.
Capacitance (C) =VQ=voltcoulomb.
Hence the correct option B.
Additional information:
One-millionth of a farad is called microfarad (μF). One-millionth of a microfarad is called a picofarad (pF). The unit of Capacitance is Farad. This unit is too big for any practical work.
To overcome this difficulty, the capacitance is measured in picofarads, microfarads. Capacitor is also called a condenser, which is a sandwich of two plates of dielectric or conducting material.
The Capacitance is a function of the area of the plates and distance between the plates, permittivity of the dielectric material between the plates of the capacitor. The reciprocal of Capacitance is called Elastance(S). When the potential difference is halved, then the quantity of charge stored in the capacitor is halved and hence the relationship between capacitance, charge and potential difference is linear.
Note: Capacitance is a passive device because it consumes power. Potential energy is stored in the capacitor because Capacitor stores charge between the plates and these charges are stationary. Therefore potential energy is stored.