Two identical capacitors, have the same capacitance C. One of them is charged to potential V₁ and the other to V₂. The negative ends of the capacitors are connected together. When the positive ends are also connected, the decrease in energy of the combined system is 

(1) $\frac{1}{4}C(V_1^2-V_2^2)$

(2) $\frac{1}{4}C(V_1^2+V_2^2)$

(3) $\frac{1}{4}C{(V_1-V_2)}^2$

(4) $\frac{1}{4}C{(V_1+V_2)}^2$

Three capacitors each of capacity 4 μF are to be connected in such a way that the effective capacitance is 6 μF. This can be done by 

(1) Connecting them in parallel

(2) Connecting two in series and one in parallel

(3) Connecting two in parallel and one in series

(4) Connecting all of them in series

Three capacitors of capacitance 3 μF are connected in a circuit. Then their maximum and minimum capacitances will be

(1) 9 μF, 1 μF

(2) 8 μF, 2 μF

(3) 9 μF, 0 μF

(4) 3 μF, 2 μF

A capacitor of capacity C₁ is charged upto V volt and then connected to an uncharged capacitor of capacity C₂. Then final potential difference across each will be 

(1) $\frac{C_{2}V}{C_1+C_2}$

(2) $\left(1+\frac{{\displaystyle C_2}}{{\displaystyle C_1}}\right)V$

(3) $\frac{C_{1}V}{C_1+C_2}$

(4) $\left(1-\frac{{\displaystyle C_2}}{{\displaystyle C_1}}\right)V$

Four identical capacitors are connected as shown in diagram. When a battery of 6 V is connected between A and B, the charge stored is found to be 1.5 μC. The value of C₁ is 

(1) 2.5 μF

(2) 15 μF

(3) 1.5 μF

(4) 0.1 μF

Two identical thin rings each of radius R meters are coaxially placed at a distance R meters apart. If Q₁ coulomb and Q₂ coulomb are respectively the charges uniformly spread on the two rings, the work done in moving a charge q from the centre of one ring to that of other is 

(1) Zero

(2) $\frac{q(Q_2-Q_1)(\sqrt{2}-1)}{\sqrt{2}.4\pi {\epsilon }_{0}R}$

(3) $\frac{q\sqrt{2}(Q_1+Q_2)}{4\pi {\epsilon }_{0}R}$

(4) $\frac{q(Q_1+Q_2)(\sqrt{2}+1)}{\sqrt{2}.4\pi {\epsilon }_{0}R}$

A non-conducting ring of radius 0.5 m carries a total charge of 1.11 × 10^–10 C distributed non-uniformly on its circumference producing an electric field $\overrightarrow{E}$ everywhere in space. The value of the line integral ${\int }_{l=\infty }^{l=0}-\overrightarrow{E}.\overrightarrow{dl}(l=0$ being centre of the ring) in volt is 

(1) + 2

(2) – 1

(3) – 2

(4) Zero

A negatively charged plate has charge density of 2 × 10^–6 C/m². The initial distance of an electron which is moving toward plate but cannot strike the plate, if it is having energy of 200 eV 

(1) 1.77 mm

(2) 3.51 mm

(3) 1.77 cm

(4) 3.51 cm

Electric potential is given by

$V=6x-8x{y}^2-8y+6yz-4z^2$

Then electric force acting on 2C point charge placed on origin will be 

(1) 2N

(2) 6N

(3) 8N

(4) 20N

Consider two points \(1\) and \(2\) in a region outside a charged sphere. Two points are not very far away from the sphere. If \(E\) and \(V\) represent the electric field vector and the electric potential, which of the following is not possible?