Also Read Similar Questions Below : 15N ⇒ A capacitor stores 0.24 coulombs at 10 volts. Its capacitance is0.024 F0.12 F0.6 F 0.8 F ⇒ Three capacitors each of the capacity C are given. The resultant capacity 2/3 C can be obtained by using themall in seriesail in paralleltwo in parallel and third in series with this combination two in series and third in parallel across this combination ⇒ A variable capacitor of 100 µF carries a charge of 0.35 µC. The capacitance is subsequently reduced to 40 pF. The voltage appearing across the capacitor after reduction of its capacitance will be8750 V4350V2000 V 1500V ⇒ The condensors of 20 µFand 40 µF capacitance are connected in series across a 90 V supply. After charging, they are removed from the supply and are connected in parallel with positive terminals connected together and similarly the negative terminals. Then the voltage across them wiIl be90 V60 V40 V 20 V ⇒ A capacitor charged to 200 V has 2000 µC of charge. The value of capacitanet. will be10 F10 µF100 µF 1000 µF ⇒ Energy stored in the electric field of a
capacitor C when charged from a D.C
source of voltage V is equal to____ joules ⇒ A paper capacitor is usually available in the form oftubesrolled foildisc meshed plates ⇒ The capacitor charged up to 5 ms, as per the current profile given in the figure, is connected across an inductor of 0.6 mH. Then the value of voltage across the capacitor after 1 µs will approximately be18.8 V23.5 V-23.5 V -30.6 V ⇒ For preventing the generation of static charge on rubber or flat leathersurface is moistened.conductive dressing is done.oil compound dressing is done. any of the above. ⇒ ____at a point is equal to the negative potential gradient at that point.Electric intensityElectric fluxMagnetic flux Magnetic flux density ⇒ If the dielectric of a capacitor is replaced by a conducting material thecapacitor will get heated up owing to eddy currents.plates will get short circuited.capacitor can store infinite charge capacitance will become very high. ⇒ The value of E within the field due to a pointcharge can be found with the help ofFaraday's lawsKirchhoff's lawsCoulomb's laws none of the above ⇒ The area of plates of the parallel plate
capacitor, to obtain capacity of 0.3 x 10-3 µF if they are separated by a distance
of 10mm and a dielectric between
them of permittivity = 2.5, will be ⇒ A gang condenser is apolarised capacitorvariable capacitorceramic capacitor none of the above ⇒ The unit of dielectric strength is given byV/m V2/m m/Vm/V2 ⇒ Two capacitors each having capacitance C and breakdown voltage V are joined in series. The capacitance and breakdown voltage of the combination will be2 C and 2 VC/2 and V/22 C and V/2 C/2 and 2 V ⇒ Out of the following capacitors of identical rating which one will have the smallest dimensions?Aluminium foil capacitorMica capacitorCeramic capacitor Paper capacitor ⇒ The ohmmeter reading for a short circuited capacitor isinfinityfew kilo ohmsfew megaohms zero ⇒ TIte capacitance G is charged througi a resistance R. The time constant of the charging circuit is given byC/R1/RCRC R/C ⇒ The mass of an electron is equal to ⇒ Paper capacitors usually have a tolerance of±5%±10%±15% ±20% ⇒ The mínimumvalue of potential gradient in a cable occurs ininsulationconductorouter sheath uniformly all over ⇒ For which of the following parameter variation, the capacitance of the capacitor remains unaffected?Distance between platesArea of theplatesNature of dielectric Thickness of the plates ⇒ Which of the following medium will have highest value of relative permittivity?WaterGlassMica Paper ⇒ When a dielectric slab is introduced in a parallel plate capacitor, the potential difference between plates willremain unchargeddecreaseincrease become zero ⇒ Coulomb' s law for the force between electric charges most closely resembles withNewton's law of motion.Law of conservation of energy.Gauss's theorem. Newton's law of gravitation ⇒ Across the surface of a charged conductor, the electricfield is éontinuouspotential is discontinuousfield is discontinuous none of the above ⇒ Dielectric strength of mica is10 to 20 kV/mm30 to 50 kV/mm50 to 200 kV/mm 300 to 500 kV/mm ⇒ The electric potential due to an electric dipole of length l at a point distance r away from it will be doubled if thelength l of the dipole is doubled.r is doubled.r is halved. l is halved.
This is incorrect. Capacitance is \$C=\large\epsilon\frac{A}{d}\$, where \$\large\epsilon\$ = the permittivity of the medium (usually vacuum or air, \$\epsilon = 8.85*10^{-12}\$). \$C\$ can also be defined at \$C=\frac{Q}{V}\$, where \$Q\$ is the charge on one plate. In a parallel plate capacitor, \$A\$ and \$d\$ are clearly obvious. Imagine that \$d\$ increases by separating the plates -- the capacitance decreases. In the limit, as you separate the plates, the capacitance will not decrease to 0, but to a limiting value - see http://www.vias.org/matsch_capmag/matsch_caps_magnetics_chap2_10.html |