Download App

Electrostatic Potential and Capacitance — Physics STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 SciencePhysicsElectrostatic Potential and Capacitance2 Marks
Question
A parallel plate capacitor with air between the plates has a capacitance of 8 pF. The separation between the plates is now reduced by half and the space between them is filled with a medium of dielectric constant 5. Calculate the value
of capacitance of the capacitor in the second case.
✓

Answer

$\text{c} =\frac{\text{A}\varepsilon_{\circ}\varepsilon_{r}}{\text{d}}$ or $\frac{\text{k}\varepsilon_{\circ}\text{A}}{\text{d}}$$\text{c} = 5\times\frac{\varepsilon_{\circ}\text{A}}{\text{d}/2}$
$\text{c} = 10 \bigg(\frac{\text{A}\varepsilon_{\circ}}{\text{d}}\bigg) = 10 \times8 = 80\text{pf}$.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "2 Marks Questions" from Electrostatic Potential and Capacitance→Electrostatic Potential and Capacitance — all question types→Physics STD 12 Science question papers→Gujarat Board STD 12 Science question papers→Gujarat Board question paper generator→

Similar questions

The susceptibility of magnesium at 300 K is $1.2 \times 10^{-5}$. At what temperature will the susceptibility increase to $1.8 \times 10^{-5}$ ?
→
Two metal strips, each of length l, are clamped parallel to each other on a horizontal floor with a separation b between them. A wire of mass m lies on them perpendicularly, as shown in A vertically-upward magnetic field of strength B exists in the space. The metal strips are smooth but the coefficient of friction between the wire and the floor is $\mu.$ A current i is established when the switch S is closed at the instant t = 0. Discuss the motion of the wire after the switch is closed. How far away from the strips will the wire reach?
→
An electric dipole is placed inside a closed surface, whose dipole moment is $20 \times 10^{-6}$ coulomb$-$meter. What will be the electric flux emerging out of this surface?
→
Derive an expression for drift velocity of free electrons in a conductor in terms of relaxation time.
→
When can the internal resistance of the cell can be neglected? Derive the formula for the current when cell is connected to the external resistance $R$.
→
A person wears glasses of power -2.5D. Is the person farsighted or nearsighted? What is the far point of the person without the glasses?
→
The instantaneous voltage from an ac source is given by $\text{E}=300\sin314\text{t};$ what is the rms voltage of the source.
→
Plot a graph showing the variation of coulomb force (F) versus$\bigg(\frac{1}{\text{r}^{2}}\bigg)$; where r is the distance between the two charges of each pair of charges: (1 μC, 2 μC) and (2 μC, – 3 μC). Interpret the graphs obtained.
→
The selling rate of a radioactive isotope is decided by its activity. What will be the second-hand rate of a one month old $\text{ }^{32}\text{P}\big(\text{t}_{\frac{1}{2}}=14.3\text{days}\big)$ source if it was originally purchased for 800 rupees?
→
Explain Rutherford's argument for scattered $\alpha$-particles.
→