SATHEE: Electrostatics Question 258

Electrostatics Question 258

Question: A piece of cloud having area $25 \times 10^{6} m^{2}$ and electric potential of $10^{5}$ volts. If the height of cloud is $0.75 k m$ , then energy of electric field between earth and cloud will be [RPET 1997]

Options:

A) V

B) 2V

C) 4V

D) ? 2V

Show Answer

Answer:

Correct Answer: A

Solution:

In case of a charged conducting sphere

$V_{inside} = V_{centre} = V_{surface} = \frac{1}{4 π ε_{o}} . \frac{q}{R}$ ,

$V_{outside} = \frac{1}{4 π ε_{0}} . \frac{q}{r}$

If a and b are the radii of sphere and spherical shell respectively, then potential at their surface will be $V_{sphere} = \frac{1}{4 π ε_{0}} . \frac{Q}{a}$ and $V_{shell} = \frac{1}{4 π ε_{0}} . \frac{Q}{b}$

$∴$

$V = V_{sphere} - V_{shell} = \frac{1}{4 π ε_{0}} . [\frac{Q}{a} - \frac{Q}{b}]$

Now when the shell is given charge (?3Q), then the potential will be

$V_{sphere}^{'} = \frac{1}{4 π ε_{0}} [\frac{Q}{a} + \frac{(- 3 Q)}{b}],$

$V_{shell}^{'} = \frac{1}{4 π ε_{0}} [\frac{Q}{b} + \frac{(- 3 Q)}{b}]$

$∴$

$V_{sphere}^{'} - V_{shell}^{'} = \frac{1}{4 π ε_{0}} [\frac{Q}{a} - \frac{Q}{b}] = V$

Electrostatics Question 258

Question: A piece of cloud having area $25 \times 10^{6} m^{2}$ and electric potential of $10^{5}$ volts. If the height of cloud is $0.75 k m$ , then energy of electric field between earth and cloud will be [RPET 1997]

Options:

Answer:

Solution:

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Electrostatics Question 258

Question: A piece of cloud having area 25×106m2 and electric potential of 105 volts. If the height of cloud is 0.75km , then energy of electric field between earth and cloud will be [RPET 1997]

Options:

Answer:

Solution:

Engineering Preparation

Medical Preparation

NCERT Books & Solutions

Important Resources

Other Resources

Syllabus

Test Platform

Sample Mock Test

Mentorship

NCERT Exercise Video Solution

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Question: A piece of cloud having area $25 \times 10^{6} m^{2}$ and electric potential of $10^{5}$ volts. If the height of cloud is $0.75 k m$ , then energy of electric field between earth and cloud will be [RPET 1997]