JEE Mains · Physics · STD 12 - 2. Electric potential and capacitance
A capacitor P with capacitance \( 10\times10^{-6} F \) is fully charged with a potential difference of 6.0 V and disconnected from the battery. The charged capacitor P is connected across another capacitor Q with capacitance \( 20\times10^{-6} F \). The charge on capacitor Q when equilibrium is established will be \( \alpha\times10^{-5} C \).(assume capacitor \(Q\) does not have any charge initially),The value of \( \alpha \) is __________ .
- A 2
- B 6
- C 3
- D 4
Answer & Solution
Correct Answer
(D) 4
Step-by-step Solution
Detailed explanation
\(V=\frac{C_1 V_1+C_2 V_2}{C_1+C_2}=\frac{10^{-5} \times 6+0}{3 \times 10^{-5}}\) V=2 volt \(Q _2= C _2 V=2 \times 10^{-5} \times 2=4 \times 10^{-5} C\)
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 ring and a solid sphere rotating about an axis passing through their centers have same radii of gyration. The axis of rotation is perpendicular to plane of ring. The ratio of radius of ring to that of sphere is \(\sqrt{\frac{2}{x}}\). The value of \(x\) is \(.......\)JEE Mains 2023 Medium
-

Two identical circular loops P and Q each of radius r are lying in parallel planes such that they have common axis. The current through P and Q are I and 4I respectively in clockwise direction as seen from O . The net magnetic field at O is:JEE Mains 2026 Easy - Two light beams of intensities \(4\,I\) and \(9\,I\) interfere on a screen. The phase difference between these beams on the screen at point \(A\) is \(zero\) and at point \(B\) is \(\pi\). The difference of resultant intensities, at the point \(A\) and \(B\), will be \(....I\).JEE Mains 2022 Medium
- From \(18\) m height above the ground a ball is dropped from rest. The height above the ground at which the magnitude of velocity equal to the magnitude of acceleration (in the same set of units) due to gravity is _____ m.
(Take \(g = 10\) m/s\(^2\) and neglect the air resistance)JEE Mains 2026 Medium - An object of mass 8 kg is hanging from one end of a uniform rod \(C D\) of mass 2 kg and length 1 m pivoted at its end \(C\) on a vertical wall as shown in figure. It is supported by a cable \(A B\) such that the system is in equilibrium. The tension in the cable is:
(Take \(g=10 m s ^{-2}\) )
JEE Mains 2023 Medium - Which of the following statements is false?JEE Mains 2017 Easy
More PYQs from JEE Mains
- Let \(S _{1}, S _{2}\) and \(S _{3}\) be three sets defined as \(S _{1}=\{ z \in C :| z -1| \leq \sqrt{2}\}\) ; \(S _{2}=\{ z \in C : \operatorname{Re}((1- i ) z ) \geq 1\}\) ; \(S _{3}=\{ z \in C : \operatorname{Im}( z ) \leq 1\}\) Then the set \(S _{1} \cap S _{2} \cap S _{3}\)JEE Mains 2021 Hard
- The mean of the numbers \(a, b, 8,5,10\) is \(6\) and their variance is \(6.8\). If \(M\) is the mean deviation of the numbers about the mean, then \(25\; M\) is equal toJEE Mains 2022 Hard
- A wire of length \(2\,L\) is made by joining two wires \(A\) and \(B\) of same lengths but different radii \(r\) and \(2r\) and made of the same material. It is vibrating at a frequency such that the joint of the two wires forms a node. If the number of antinodes in wire \(A\) is \(p\) and that in \(B\) is \(q\) then the ratio \(p : q\) is
JEE Mains 2019 Hard - The reading of pressure metre attached with a closed pipe is \(4.5 \times 10^4 \mathrm{~N} / \mathrm{m}^2\). On opening the valve, water starts flowing and the reading of pressure metre falls to \(2.0 \times 10^4 \mathrm{~N} / \mathrm{m}^2\). The velocity of water is found to be \(\sqrt{\mathrm{V}} \mathrm{m} / \mathrm{s}\). The value of \(\mathrm{V}\) is__________JEE Mains 2024 Hard
- A particle moves in a straight line so that its displacement \(x\) at any time \(t\) is given by \(x^2=1+t^2\). Its acceleration at any time \(\mathrm{t}\) is \(\mathrm{x}^{-\mathrm{n}}\) where \(\mathrm{n}=\) _______.JEE Mains 2024 Hard
- In an \(A.P.\), the sixth terms \(a_6=2\). If the \(a_1 a_4 a_5\) is the greatest, then the common difference of the \(A.P.,\) is equal toJEE Mains 2024 Hard