Physics-DPP-6-Electrostatics

PHYSICS Topic: ELECTROSTATICS Date: 1. Three capacitors of capacitances 3μF , 9μF and 18μF are connected once in series and another time in parallel. The ratio of æçCs ö÷ equivalent capacitance in the two cases ç ÷ will be : çèCp ø÷ (a) 1 : 15 (b) 15 : 1 (c) 1 : 1 (d) 1 : 3 2. Three equal capacitors, each with capacitance C are connected as shown in figure. Then the equivalent capacitance between A and B is : (a) C (b) 3 C (c) C 3C 3 (d) 2 3. In the adjoining figure, four capacitors are shown with their respective capacities and the PD applied. The charge and the PD across the 4μF capacitors will be : (a) 600μC; 150 V (b) 300μC; 75 V (c) 800 μC; 200 V (d) 580 μC; 145 V 4. In the connections shown in the adjoining figure, the equivalent capacity between A and B will be : (a) 12μF (b) 69μF (c) 15μF (d) 10μF 5. In the following circuit, the resultant capacitance between A and B is 1μF . The value of C is : (a) 32 μF 11 (c) 23 μF 32 (b) 11 μF 32 (d) 32 μF 23 6. Four plates of the same area of cross-section are joined as shown in the figure. The distance between each plate is d. The equivalent capacity across A and B will be : (a) 2ε0 A d (b) 3ε0 A d (c) 3ε0 A 2d (d) ε0A d PHYSICS Topic: ELECTROSTATICS Date: 7. Four capacitors are connected in a circuit as shown in the figure. The effective capacitance in μF between points A and B will be : (a) 28 9 (b) 4 (c) 5 (d) 18 8. The resultant capacitance of given circuit between points P and Q is : (a) 3 C (b) 2 C C (c) C (d) 3 9. In the figure a capacitor is filled with dielectrics. The resultant capacitance is : 2ε0A é 1 1 1 ù ε0A é 1 1 1 ù (a) ê + + ú (b) ê + + ú d êK1 K2 K3 ú d êK1 K2 K3 ú ë û ë û (c) 2ε0 A [K + K + K ] (d) ε0 A é K1K2 K3 ù d 1 2 3 d êK + K 2 ú ë 1 2 û 10. A 2μF condenser is charged upto 200 V and then battery is removed. On combining this with another uncharged condenser in parallel, the potential differences between two plates are found to be 40 V. The capacity of second condenser is : (a) 2μF (b) 4μF (c) 8μF (d) 16μF 11. Two conducting charged spheres of radii R1 and R2 having charges Q1 and Q2 are respectively connected to each other. There is : (a) an increase in the energy of the system (b) no change in the energy of the system (c) always decrease in energy (d) a decrease in energy of the system unless Q1R2 = Q2 R1 PHYSICS Topic: ELECTROSTATICS Date: Answer Key 1. (a) 2. (b) 3. (d) 4. (d) 5. (d) 6. (b) 7. (a) 8. (a) 9. (d) 10. (c) 11. (d)

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