JEE Mains · Physics · STD 12 - Electric potential and capacitance
- JEE Mains 2022
- Hard
- Numerical
A composite parallel plate capacitor is made up of two different dielectric materials with different thickness \(\left(t_{1}\right.\) and \(\left.t_{2}\right)\) as shown in figure. The two different dielectric material are separated by a conducting foil \(F\). The voltage of the conducting foil is \(.....V\)

Pick an option to check your answer.
Answer & Solution
Correct Answer
(D) \(60\)
Step-by-step Solution
Detailed explanation
Capacitance of each capacitor
\(C _{1}=\frac{ A 3 \epsilon_{0}}{\frac{1}{2}}=6 A \epsilon_{0}\)
\(C _{2}= A 4 E _{0}=4 A \in_{0}\)
Equivalent capacitance
\(C _{\text {eq }}=\frac{ C _{1} C _{2}}{ C _{1}+ C _{2}} \Rightarrow \frac{24}{10} A \in_{0}\)
\(q _{\text {net }}= C _{\text {eq }}(\Delta V ) \Rightarrow 240 A \in_{0}\)
\(\Delta V _{2}=\frac{240 A \epsilon_{0}}{4 A \epsilon_{0}}=60\,V\)
\(\left(\Delta V _{2}=\text { Potential drop across } C _{2}\right)\)
\(V _{\text {foil }}=60\,V\)
More questions from Physics
- A block moving horizontally on a smooth surface with a speed of \(40\, {m} / {s}\) splits into two parts with masses in the ratio of \(1: 2\). If the smaller part moves at \(60\, {m} / {s}\) in the same direction, then the fractional change in kinetic energy is :-JEE Mains 2021 Hard
- A vector \(\vec A \) is rotated by a small angle \(\Delta \theta\) radian \(( \Delta \theta << 1)\) to get a new vector \(\vec B\) In that case \(\left| {\vec B - \vec A} \right|\) isJEE Mains 2015 Medium
- A container of fixed volume contains a gas at \(27^{\circ} \mathrm{C}\). To double the pressure of the gas, the temperature of gas should be raised to ______ \({ }^{\circ} \mathrm{C}\).JEE Mains 2025 Easy
- pendulum made of a uniform wire of cross sectional area \(A\) has time period \(T\). When an additional mass \(M\) is added to its bob, the time period changes to \(T_M\). If the Young's modulus of the material of the wire is \(Y\) then \(\frac{1}{Y}\) is equal to : (\(g\) = gravitational acceleration)JEE Mains 2015 Hard
- During the propagation of electromagnetic waves in a mediumJEE Mains 2014 Easy
- Consider a finite insulated, uncharged conductor placed near a finite positively charged conductor. The uncharged body must have a potentialJEE Mains 2013 Hard
More PYQs from JEE Mains
- The dimension of mutual inductance is ............JEE Mains 2022 Medium
- The diameter of a spherical bob is measured using a vernier callipers. \(9\) divisions of the main scale, in the vernier callipers, are equal to \(10\) divisions of vernier scale. One main scale division is \(1\, {mm}\). The main scale reading is \(10\, {mm}\) and \(8^{\text {th }}\) division of vernier scale was found to coincide exactly with one of the main scale division. If the given vernier callipers has positive zero error of \(0.04\, {cm}\), then the radius of the bob is \(...... \,\times 10^{-2} \,{cm}\)JEE Mains 2021 Hard
- A point charge \(q = 1\ \mu\text{C}\) is located at a distance \(2\text{ cm}\) from one end of a thin insulating wire of length \(10\text{ cm}\) having a charge \(Q = 24\ \mu\text{C}\), distributed uniformly along its length, as shown in figure. Force between \(q\) and wire is _______ N.
(Use \(\frac{1}{4\pi\varepsilon_0} = 9 \times 10^9\text{ N}\cdot\text{m}^2/\text{C}^2\))
JEE Mains 2026 Easy - A conducting circular loop is rotated about its diameter at a constant angular speed of 100 rad/s in a magnetic field of 0.5 T perpendicular to the axis of rotation. When the loop is rotated by 30° from the horizontal position, the induced EMF is 15.4 mV. The radius of the loop is ________ mm. (Take \( \pi=22/7 \))JEE Mains 2026 Easy