Question 179: Electrostats & Capacitance

Question

STATEMENT 1 : For practical purposes, the earth is used as a reference at zero potential in electrical circuits.
and
STATEMENT 2 : The electrical potential of a sphere of radius R with charge Q uniformly distributed on the surface is given by $${Q \over {4\pi {\varepsilon _0}R}}$$

Accepted Answer

Statement 1 is True.
The earth is used as a reference
with zero potential. The reasons are :
(i) Due to large size of the earth, its potential does
not change even if a small amount of charge is
given to the earth or taken away from it. Also, all
conductors on the earth which are not given any
external charge, are very nearly at the potential
V
e
. The choice of reference is quite arbitrary and
is largely governed by convenience.
(ii) The earth is a good conductor. It is easily accessible for electrical circuits geographically distributed over it and hence it is used as a common
reference with zero potentil.
Statement 2 is true.
V = $${Q \over {4\pi {\varepsilon _0}R}}$$
Therefore, statement 2 is correct explanation for statement 1.

Answer

Statement 1 is True, Statement 2 is True; Statement 2 is a CORRECT explanation for Statement 1

Answer

Statement 1 is True, Statement 2 is True; Statement 2 is a NOT CORRECT explanation for Statement 1

Answer

Statement 1 is True, Statement 2 is False

Answer

Statement 1 is False, Statement 2 is True

Electrostats & Capacitance

STATEMENT 1 : For practical purposes, the earth is used as a reference at zero potential in electrical circuits. and STATEMENT 2 : The electrical potential of a sphere of radius R with charge Q uniformly distributed on the surface is given by ${Q \over {4\pi {\varepsilon _0}R}}

Choose the correct answer: