Practice Test


1) The capacitance of a capacitor depends on


2) 1 F equals


3) A 900 p F capacitor is charged by 100 V battery. The electrostatic energy stored by the capacitor is


4) A 900 p F capacitor connected to a 100 V battery is disconnected from the battery and connected to another 900 pF capacitor. The electrostatic energy stored by the system is


5) A parallel plate capacitor with air between the plates has a capacitance of 8 pF. What will be the capacitance if the distance between the plates is reduced by half and the space between them is filled with a space substance of dielectric constant 6.


6) Three capacitors each of capacitance 9 pF are connected in series, across a 120 V supply. The total capacitance of the combination and the potential difference across each capacitor are respecitvely :


7) Three capacitors of capacitances 2 pF, 3 pF and 4 pF are connected in parallel across a 100 V supply. The total capacitance of combination and the charge on 3 pF capacitor are respectively :


8) The area of the plates of a 2 F parallel plate capacitor, given that the separation is 0.5 cm is:


9) The dimensions of capacitance are


10) The equivalent capacitance of the network is


11) If this capacitor is connected to a 100 V supply, what is the charge on the capacitor?


12) A 3 mm mica sheet (of dielectric constant = 6) was inserted between the plates while the voltage supply remained connected, the charge on the capacitor


13) If the mica sheet is inserted after the supply is disconnected then the voltage across the capacitor


14) The subsequent charges on the 600 pF and 200 pF capacitor are respectively.


15) The electrostatic energy lost is


16) A sheet of aluminium foil of negligible thickness is introduced between the plates of a capacitor. The capacitance of the capacitor.


17) A parallel plate condenser with oil between the plates (dielectric constant of oil K = 2) has a capacitance C . If the oil is removed, then capacitance of the capacitor becomes


18) In a parallel-plate capacitor, the region between the plates is completely filled by a dielectric slab. The capacitor is charged from a battery and then disconnected from it. The dielectric slab is now taken out. Which of the following is correct?


19) The internal and external radii of a cylindrical condenser are both doubled. Its capacity will be


20) Three identical capacitor are combined differently. For the same voltage to each combination, the one that stores the greatest energy is


21) The capacity of a parallel plate condenser is 12 pF. If the area of both the plates is doubled and the distance between them is reduced to half, the capacity of the condenser will be


22) Which one of the following methods will reduce the capacitance of a parallel plate capacitor?


23) A thin metal plate is inserted between the plates of a parallel plate capacitor of capacitance C in such a way that its edges touch the two plates. The capacitance now becomes


24) Statement 1 : If a dielectric is placed in external field then field inside dielectric will be less than applied field.
Statement 2 : Electric field will induce dipole moment opposite to field direction.


25) Statement 1 : Capacitance of a system of two conductors at finite separations, separated by some insulating medium, depends on geometry of the conductors and properties of insulating medium separating the conductors.
Statement 2 : Capacitance of a capacitor does not depend on charge stored by the capacitor.


26) In a parallel-plate capacitor, the region between the plates is filled by a dielectric slab. The capacitor is connected to a battery and the slab is taken out. Which of the following is correct?


27) A parallel plate air capacitor is charged to a potential difference V. After disconnecting the battery, the distance between the plates of the capacitor is increased using an insulating handle. As a result, potential difference between the plates


28) A parallel plate capacitor is made by stacking n equally spaced plates connected alternatively. If the capacitance between any two adjacent plates is C then the resultant capacitance is


29) What fraction of the energy drawn from the charging battery is stored in a capacitor?


30) The area of the plates of a parallel plate condenser is A and the distance between the plates is 10 mm. There are two dielectric sheets in it, one of dielectric constant 10 and thickness 6 mm and the other dielectric constant 5 and thickness 4 mm. The capacity of the condenser is


31) Statement 1 : Capacitance of a parallel plate capacitor increases if a metallic slab is introduced in between the plates of the capacitor.
Statement 2 : For same charge stored by the plates of capacitor, electrostatic potential energy of the system is more if a metallic slab is introduced in between plates of the capacitor.


32) Statement 1 : There can be potential difference between two adjacent conductors that carry the same amount of positive charge.
Statement 2 : Capacitance of a conductor depends on the size.


33) The work done by the battery is


34) Thermal energy produced in the circuit is