Two spherical conductors B and C having equal | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(D) Initially,the force between $B$ and $C$ is given by Coulomb's law: $F = k \frac{Q^2}{r^2}$.When the uncharged conductor (let's call it $D$) is bro

Vedclass · Accepted Answer

$3F/8$

Vedclass · Answer

(D) Initially,the force between $B$ and $C$ is given by Coulomb's law: $F = k \frac{Q^2}{r^2}$.When the uncharged conductor (let's call it $D$) is brought in contact with $B$,the charge $Q$ is shared equally between them because they have equal radii. Thus,the charge on $B$ becomes $Q_B = Q/2$.Next,the conductor $D$ (now carrying charge $Q/2$) is brought in contact with $C$ (which has charge $Q$). The total charge $(Q/2 + Q) = 3Q/2$ is shared equally between $C$ and $D$. Thus,the new charge on $C$ becomes $Q_C = (3Q/2) / 2 = 3Q/4$.The new force of repulsion between $B$ and $C$ is $F' = k \frac{Q_B \cdot Q_C}{r^2} = k \frac{(Q/2) \cdot (3Q/4)}{r^2} = \frac{3}{8} \left( k \frac{Q^2}{r^2} \right) = \frac{3}{8} F$.

Similar Questions

What should be the equal charge on helium-filled balloons as shown in the figure?

Three charges are placed as shown in the figure. The magnitude of $q_1$ is $2.00\, \mu C$,but its sign and the value of the charge $q_2$ are not known. Charge $q_3$ is $+4.00\, \mu C$,and the net force on $q_3$ is entirely in the negative $x-$ direction. The magnitude of $q_2$ is

$A$ point charge $Q$ is placed at the center of the line joining two equal point charges $+q$ and $+q$. The value of $Q$ if the system of the charges is in equilibrium,is

Electric charges of $1 \mu C, -1 \mu C$ and $2 \mu C$ are placed in air at the corners $A, B$ and $C$ respectively of an equilateral triangle $ABC$ having a side length of $10 \ cm$. The resultant force on the charge at $C$ is: (in $N$)

Two point charges $+q_1$ and $+q_2$ repel each other with a force of $100 \ N$. $q_1$ is increased by $10 \%$ and $q_2$ is decreased by $10 \%$. If they are kept at their original positions, the change in the force of repulsion between them is:

Vedclass Test Series

Exam Paper Generator

Online Exam Module