Question 951: Electrostats & Capacitance

Question

Charges +q and $$-$$q are placed at points A and B respectively which are a distance 2L apart, C is the midnight between A and B. The work done in moving a charge + Q along the semicircle CRD is

Accepted Answer

Potential at C = V
C
= 0
Potential at D = V
D
$$ = k\left( {{{ - q} \over L}} ight) + {{kq} \over {3L}} =  - {2 \over 3}{{kq} \over L}$$
Potential difference
V
D
Ã¢ÂÂ V
C
$$ =  - {2 \over 3}{{kq} \over L} = {1 \over {4\pi {\varepsilon _0}}}\left( { - {2 \over 3}.{q \over L}} ight)$$
$$ \Rightarrow $$ Work done = Q (V
D
Ã¢ÂÂ V
C
)
$$ =  - {2 \over 3} 	imes {1 \over {4\pi {\varepsilon _0}}}{{qQ} \over L} = {{ - qQ} \over {6\pi {\varepsilon _0}L}}$$

Answer

$${{qQ} \over {2\pi {\varepsilon _0}L}}$$

Answer

$${{qQ} \over {6\pi {\varepsilon _0}L}}$$

Answer

$$-$$ $${{qQ} \over {6\pi {\varepsilon _0}L}}$$

Answer

$${{qQ} \over {4\pi {\varepsilon _0}L}}$$

Electrostats & Capacitance

Charges +q and $-$q are placed at points A and B respectively which are a distance 2L apart, C is the midnight between A and B. The work done in moving a charge + Q along the semicircle CRD is

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