JEE Mains · Physics · STD 12 - 2. Electric potential and capacitance
In the figure shown, after the switch \(‘S’\) is turned from position \(‘A’\) to position \(‘B’\), the energy dissipated in the circuit in terms of capacitance \(‘C’\) and total charge \(‘Q’\) is

- A \(\frac{1}{8}\frac{{{Q^2}}}{C}\)
- B \(\frac{3}{8}\frac{{{Q^2}}}{C}\)
- C \(\frac{5}{8}\frac{{{Q^2}}}{C}\)
- D \(\frac{3}{4}\frac{{{Q^2}}}{C}\)
Answer & Solution
Correct Answer
(B) \(\frac{3}{8}\frac{{{Q^2}}}{C}\)
Step-by-step Solution
Detailed explanation
Before switch is shifted: Energy stored, \(\mathrm{U}_{1}=\frac{1}{2} \mathrm{CE}^{2}\) and charge stored, \(Q=C E\) After switch is shifted: \(V_{M}-V_{N}=\frac{Q}{4 C}=\frac{C E}{4 C}=\frac{E}{4}\) Energy stored,…
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
- Consider a water tank as shown in the figure. It's cross-sectional area is \(0.4\, m ^{2}\). The tank has an opening \(B\) near the bottom whose cross-section area is \(1\, cm ^{2}\). A load of \(24\, kg\) is applied on the water at the top when the height of the water level is \(40\, cm\) above the bottom, the velocity of water coming out the opening \(B\) is \(v\, ms ^{-1}\). The value of \(v\), to the nearest integer, is ......\(m/s\). [Take value of \(g\) to be \(10 \,ms ^{-2}\) ]
JEE Mains 2021 Hard - A compound microscope consists of an objective lens of focal length \(1 \,cm\) and an eye piece of focal length \(5 \,cm\) with a separation of \(10 \,cm\) The distance between an object and the objective lens, at which the strain on the eye is minimum is \(\frac{ n }{40}\, cm .\) The value of \(n\) is\(....\)JEE Mains 2020 Medium
- A uniform electric field \(\vec E\) exists between the plates of a charged condenser. A charged particle enters the space between the plates and perpendicular to \(\vec E\) . The path of the particle between the plates is aJEE Mains 2013 Hard
- Four point charges \(-q, +q, +q\) and \(-q\) are placed on \(y\) axis at \(y = -2d\), \(y = -d, y = +d\) and \(y = +2d\), respectively. The magnitude of the electric field \(E\) at a point on the \(x -\) axis at \(x = D\), with \(D > > d\), will vary asJEE Mains 2019 Hard
- \(27\) similar drops of mercury are maintained at \(10 \,V\) each. All these spherical drops combine into a single big drop. The potential energy of the bigger drop is ....... times that of a smaller drop.JEE Mains 2021 Hard
- A ball of mass \(200\,g\) rests on a vertical post of height \(20\,m\). A bullet of mass \(10\,g\), travelling in horizontal direction, hits the centre of the ball. After collision both travels independently. The ball hits the ground at a distance \(30\,m\) and the bullet at a distance of \(120\,m\) from the foot of the post. The value of initial velocity of the bullet will be \(............m/s\) (if \(\left.g =10 m / s ^2\right)\)JEE Mains 2023 Hard
More PYQs from JEE Mains
- If e is the electronic charge, \(c\) is the speed of light in free space and \(h\) is Planck's constant, the quantity \(\frac{1}{4 \pi \varepsilon_{0}} \frac{| e |^{2}}{h c}\) has dimensions of .......JEE Mains 2021 Hard
- \(A\) and \(B\) alternately throw a pair of dice. \(A\) wins if he throws a sum of 5 before \(B\) throws a sum of 8 , and \(B\) wins if he throws a sum of 8 before \(A\) throws a sum of 5 . The probability, that \(A\) wins if A makes the first throw, isJEE Mains 2025 Medium
- The distance of the point \((2,3)\) from the line \(2 \mathrm{x}-\) \(3 \mathrm{y}+28=0\), measured parallel to the line \(\sqrt{3} \mathrm{x}-\mathrm{y}+1=0\), is equal toJEE Mains 2024 Medium
- A uniform rectangular thin sheet \(ABCD\) of mass \(M\) has length \(a\) and breadth \(b\), as shown in the figure. If the shaded portion \(HBGO\) is cut off, the coordinates of the centre of mass of the remaining portion will be
JEE Mains 2019 Hard - Let \(S=\left\{\theta \in[-\pi, \pi]-\left\{\pm \frac{\pi}{2}\right\}: \sin \theta \tan \theta+\tan \theta=\sin 2 \theta\right\} \text {. }\) If \(T =\sum_{\theta \in S } \cos 2 \theta\), then \(T + n ( S )\) is equalJEE Mains 2022 Hard
- Suppose Anil's mother wants to give \(5\) whole fruits to Anil from a basket of \(7\) red apples, \(5\) white apples and \(8\) oranges. If in the selected \(5\) fruits, at least \(2\) orange, at least one red apple and at least one white apple must be given, then the number of ways, Anil's mother can offer \(5\) fruits to Anil is \(........\)JEE Mains 2023 Hard