Question:
A parallel plate capacitor consists of two circular plates of radii 5 cm and 10 cm. The centres of the two plates are kept on the same straight line with a separation of 'd' and the plates are completely immersed in a liquid of dielectric constant 18. If the capacitance of the capacitor immersed in the liquid is 250 pF, then the value of 'd' is
A parallel plate capacitor consists of two circular plates of radii 5 cm and 10 cm. The centres of the two plates are kept on the same straight line with a separation of 'd' and the plates are completely immersed in a liquid of dielectric constant 18. If the capacitance of the capacitor immersed in the liquid is 250 pF, then the value of 'd' is
Show Hint
Only overlapping area of plates contributes to capacitance.
Updated On: Jun 22, 2026
- 5 mm
- 10 mm
- 2.5 mm
- 7.5 mm \bigskip
Show Solution
Verified By Collegedunia
The Correct Option is B
Solution and Explanation
Concept:
Capacitance of parallel plate capacitor:
\[
C = \frac{K \varepsilon_0 A}{d}
\]
Effective overlapping area is limited by smaller plate.
---
Step 1: Find effective area.
\[ A = \pi r^2 = \pi (0.05)^2 = 0.0025\pi \] ---
Step 2: Use capacitance formula.
\[ 250 \times 10^{-12} = \frac{18 \times 8.85 \times 10^{-12} \times 0.0025\pi}{d} \] ---
Step 3: Solve for d.
\[ d \approx 10 \times 10^{-3}~m = 10~mm \] --- Final Answer: \[ (B)\ 10~mm \]
Step 1: Find effective area.
\[ A = \pi r^2 = \pi (0.05)^2 = 0.0025\pi \] ---
Step 2: Use capacitance formula.
\[ 250 \times 10^{-12} = \frac{18 \times 8.85 \times 10^{-12} \times 0.0025\pi}{d} \] ---
Step 3: Solve for d.
\[ d \approx 10 \times 10^{-3}~m = 10~mm \] --- Final Answer: \[ (B)\ 10~mm \]
Was this answer helpful?
0
0
Top TS EAMCET Physics Questions
- A wooden box lying at rest on an inclined surface of a wet wood is held at static equilibrium by a constant force $F$ applied perpendicular to the incline. If the mass of the box is $1\,kg$, the angle of inclination is $30^{\circ}$ and the coefficient of static friction between the box and the inclined plane is $0.2$, the minimum magnitude of $\vec{F}$ is (Use $ g = 10\,m/s^2$)
- A metre scale made of steel reads accurately at $25^{\circ} C$ . Suppose in an experiment an accuracy of $0.06\, mm$ in $1\,m$ is required, the range of temperature in which the experiment can be performed with this metre scale is (coefficient of linear expansion of steel is $ 11 \times 10^{-6} /^{\circ} \, C$ )
- Consider a solenoid carrying current supplied by a DC source with a constant emf containing iron core inside it. When the core is pulled out of the solenoid, the change in current will
- A parallel beam of light of intensity \(I_0\) is incident on a coated glass plate. If \(25\%\) of the incident light is reflected from the upper surface and \(50\%\) of light is reflected from the lower surface of the glass plate, the ratio of maximum to minimum intensity in the interference region of the reflected light is
- A thermocol box has a total wall area (including the lid) of $1.0 m ^{2}$ and wall thickness of $3 cm$. It is filled with ice at $0^{\circ} C$. If the average temperature outside the box is $30^{\circ} C$ throughout the day, the amount of ice that melts in one day is [Use $K_{\text {thermocol }}=0.03 W / mK$ $.L_{\text {fusion (ice) }}=3.00 \times 10^{5} J / kg ]$
View More Questions
Top TS EAMCET Capacitors and Capacitance Questions
If the electrical potential at a point on the surface of a hollow conducting sphere of radius R is V, then the electric potential at a point which is at a distance R/3 from the centre of the sphere is:
- If half of the space between the plates of a parallel plate capacitor is filled with a medium of dielectric constant 4, the capacitance is \( C_1 \). If one-third of the space between the plates of the capacitor is filled with the medium of dielectric constant 4, the capacitance is \( C_2 \). If in both cases, the dielectric is placed parallel to the plates of the capacitor, then \( C_1 : C_2 \) is:
A capacitor of capacitance (4.0 ± 0.2) μF is charged to a potential of (10.0 ± 0.1) V. The charge on the capacitor is:
Top TS EAMCET Questions
- A bag contains $5$ red balls, $3$ black balls and $4$ white balls are drawn at random. The probability that they are not of same colour is
- If $cosec\, \theta - \cot \theta = 2017$, then quadrant in which $\theta $ lies is
- If $a$ is a unit vector, then $| a \times \hat{ i }|^{2}+| a \times \hat{ j }|^{2}+| a \times \hat{ k }|^{2}=$
- $A$ straight line makes an intercept on the $Y$-axis twice as long as that on $X$-axis and is at a unit distance from the origin. Then the line is represented by the equations
- Let $S$ and $S'$ be the foci of an ellipse and B be one end of its minor axis. If $SBS'$ is an isosceles right angled triangle then the eccentricity of the ellipse is
View More Questions