JEE Mains · Physics · STD 12 - 2. Electric potential and capacitance
A parallel plate capacitor with air between the plate has a capacitance of \(15 pF\). 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 \(\frac{ x }{4}\,pF\).The value of \(x\) is \(............\)
- A \(10.5\)
- B \(1.05\)
- C \(105\)
- D \(108\)
Answer & Solution
Correct Answer
(C) \(105\)
Step-by-step Solution
Detailed explanation
\(C _0=\frac{\in_0 A }{ d }=15\,pF\) \(C =\frac{ K \in_0 A }{2 d }=\frac{3.5}{2} \times 15\,pF\) \(=\frac{105}{4}\,pF\)
See the Complete Solution
Get step-by-step explanations for this and 2.5 Lakh+ more JEE, NEET & CET questions.
- Unlock all solutions
- Practice the full chapter
- Track accuracy across PYQs
4.8 rated on Google Play · 14,000+ reviews
More questions from Physics
- A uniform electric field of \(10\,N / C\) is created between two parallel charged plates (as shown in figure). An electron enters the field symmetrically between the plates with a kinetic energy \(0.5\,eV\). The length of each plate is \(10\,cm\). The angle \((\theta)\) of deviation of the path of electron as it comes out of the field is \(.........\)(in degree).
JEE Mains 2023 Hard - The truth table for this given circuit is _______.
JEE Mains 2024 Hard - Substance \(A\) has atomic mass number \(16\) and half life of \(1\) day. Another substance \(B\) has atomic mass number \(32\) and half life of \(\frac{1}{2}\) day. If both \(A\) and \(B\) simultaneously start undergo radio activity at the same time with initial mass \(320\,g\) each, how many total atoms of \(A\) and \(B\) combined would be left after \(2\) days \(.........\times 10^{24}\)JEE Mains 2023 Medium
- From the top of a tower, a ball is thrown vertically upward which reaches the ground in \(6 \,s\). A second ball thrown vertically downward from the same position with the same speed reaches the ground in \(1.5\, s\). A third ball released, from the rest from the same location, will reach the ground in........ \(s\).JEE Mains 2022 Hard
- A refrigerator consumes an average \(35\, {W}\) power to operate between temperature \(-10^{\circ} {C}\) to \(25^{\circ} {C}\). If there is no loss of energy then how much average heat per second does it transfer? (in \({J} / {s}\))JEE Mains 2021 Medium
- A ball is thrown vertically upward with an initial velocity of \(150\,m / s\). The ratio of velocity after \(3\,s\) and \(5\,s\) is \(\frac{x+1}{x}\). The value of \(x\) is \(...........\) Take \(\left(g=10\,m / s ^2\right)\)JEE Mains 2023 Medium
More PYQs from JEE Mains
- The length of the perpendicular drawn from the point \((2, 1, 4)\) to the plane containing the lines \(\vec r = \left( {\hat i + \hat j} \right) + \lambda \left( {\hat i + 2\hat j - \hat k} \right)\,\) and \(\vec r = \left( {\hat i + \hat j} \right) + \mu \left( { - \hat i + \hat j - 2\hat k} \right)\) isJEE Mains 2019 Hard
- Let \(H: \dfrac{x^2}{a^2}-\dfrac{y^2}{b^2}=1\) be a hyperbola such that the distance between its foci is \(6\) and the distance between its directrices is \(\dfrac{8}{3}\). If the line \(x=\alpha\) intersects the hyperbola \(H\) at the points \(A\) and \(B\) such that the area of the triangle \(AOB\) is \(4\sqrt{15}\), where \(O\) is the origin, then \(\alpha^2\) equalsJEE Mains 2026 Medium
- The distance between two consecutive points with phase difference of \(60^{\circ}\) in a wave of frequency \(500\,Hz\) is \(6.0\,m\). The velocity with which wave is traveling is \(.........km / s\)JEE Mains 2023 Hard
- Let \(y=y(x)\) be the solution curve of the differential equation secy \(\frac{d y}{d x}+2 x \sin y=x^3 \cos y\), \(y(1)=0\). Then \(y(\sqrt{3})\) is equal to :JEE Mains 2024 Hard
- Let \(f: R \rightarrow R\) be a continuous function such that \(f(x)+f(x+1)=2,\) for all \(x \in R\). If \(I _{1}=\int_{0}^{8} f( x ) d x\) and \(I _{2}=\int_{-1}^{3} f( x ) d x ,\) then the value of \(I _{1}+2 I _{2}\) is equal to...........JEE Mains 2021 Hard
- Figure represents the extension (\(\Delta l\)) of a wire of length \(1\) meter, suspended from the ceiling of the room at one end with a load \(W\) connected to the other end. If the cross-sectional area of the wire is \(10^{-5}\) m\(^2\) then the Young's modulus of the wire is __________ N/m\(^2\).
JEE Mains 2026 Medium