Sign in
12thPass logo
New chatPYQ LibraryDoubtsRank report
Sign in to see Recents

Your guest activity stays on this device

Sign in to save progress →
Sign in

Capacitor question

2023 · 11 Apr · Shift 2 · Q50
Guest · filters and generic practice availableBrowsing as a guest · PYQ filters and generic practice are available. Sign in only for personalised features and saved progress.
  1. PYQ Library
  2. /JEE Main
  3. /Physics
  4. /Capacitor
  5. /2023 · 11 Apr · Shift 2 · Q50

Capacitor question

2023 · 11 Apr · Shift 2 · Q50

JEE MainPhysicsCapacitorMCQ+4 / −1
A capacitor of capacitance C\mathrm{C}C is charged to a potential V. The flux of the electric field through a closed surface enclosing the positive plate of the capacitor is :
  1. A
    Zero
  2. B
    CVε0\frac{C V}{\varepsilon_{0}}ε0​CV​
  3. C
    CV2ε0\frac{C V}{2 \varepsilon_{0}}2ε0​CV​
  4. D
    2CVε0\frac{2 C V}{\varepsilon_{0}}ε0​2CV​
View written solutionFree

Correct answer: B

  1. Charge on the capacitor

For a capacitor of capacitance CCC charged to potential difference VVV, the magnitude of charge on each plate is

Q=CVQ = CVQ=CV

So the positive plate carries charge +CV+CV+CV.

  1. Apply Gauss's law

The electric flux through any closed surface is given by

Φ=∮E⃗⋅dA⃗=Qenclosedε0\Phi = \oint \vec E \cdot d\vec A = \frac{Q_{\text{enclosed}}}{\varepsilon_0}Φ=∮E⋅dA=ε0​Qenclosed​​

If the closed surface encloses the positive plate of the capacitor, then the enclosed charge is

Qenclosed=+CVQ_{\text{enclosed}} = +CVQenclosed​=+CV

Hence,

Φ=CVε0\Phi = \frac{CV}{\varepsilon_0}Φ=ε0​CV​

  1. Match with the options

The correct option is:

CVε0\boxed{\frac{CV}{\varepsilon_0}}ε0​CV​​

So, Option B is correct.

PreviousNext

More from Capacitor

  • In the given circuit, C1​=2μF,C2​=0.2μF,C3​=2μF,C4​=4μF,C5​=2μF,C6​=2μF, The charge… Includes diagram2023 · Numerical
  • In the network shown below, the charge accumulated in the capacitor in steady state will be: Includes diagram2023 · MCQ
  • In the circuit shown, the energy stored in the capacitor is n μJ. The value of n is ​ Includes diagram2023 · Numerical
  • In the given figure the total charge stored in the combination of capacitors is 100 μC. The value of ' x ' is ​. Includes diagram2023 · Numerical
  • A parallel plate capacitor with air between the plate has a capacitance of 15pF. The separation between the plate becomes twice and the space between them is filled with a medium of dielectric constant 3.5. Then the capacitance becomes 4x​…2023 · Numerical
  • A parallel plate capacitor has plate area 40 cm 2 and plates separation 2 mm. The space between the plates is filled with a dielectric medium of a thickness 1 mm and dielectric constant 5. The capacitance of the system is :2023 · MCQ
  • A capacitor has capacitance 5 μ F when it's parallel plates are separated by air medium of thickness d. A slab of material of dielectric constant 1.5 having area equal to that of plates but thickness 2d​ is inserted between…2023 · Numerical
  • A capacitor of capacitance 900μF is charged by a 100 V battery. The capacitor is disconnected from the battery and connected to another uncharged identical capacitor such that one plate of uncharged capacitor…2023 · Numerical