JEE Mains · Physics · STD 12 - Electric potential and capacitance
- JEE Mains 2025
- Medium
- MCQ
A capacitor, \(C_1=6 \mu \mathrm{~F}\) is charged to a potential difference of \(\mathrm{V}_0=5 \mathrm{~V}\) using a 5 V battery. The battery is removed and another capacitor, \(\mathrm{C}_2=12 \mu \mathrm{~F}\) is inserted in place of the battery. When the switch 'S' is closed, the charge flows between the capacitors for some time until equilibrium condition is reached. What are the charges \(\left(q_1\right.\) and \(\left.q_2\right)\) on the capacitors \(C_1\) and \(C_2\) when equilibrium condition is reached.

Pick an option to check your answer.
Answer & Solution
Correct Answer
(A) \(q_1=10 \mu \mathrm{C}, \mathrm{q}_2=20 \mu \mathrm{C}\)
Step-by-step Solution
Detailed explanation

\(\mathrm{q}_1^{\prime}=6 \times 5=30 \mu \mathrm{C}\)
Finally

\(\begin{aligned} & 6 \mathrm{~V}_{\mathrm{C}}+12 \mathrm{~V}_{\mathrm{c}}=30+0 \\ & 18 \mathrm{~V}_{\mathrm{C}}=30 \\ & \mathrm{~V}_{\mathrm{C}}=\frac{30}{18}=\frac{5}{3} \mathrm{Volt} \\ & \Rightarrow \mathrm{q}_1=\frac{6 \times 5}{3}=10 \mu \mathrm{C} \\ & \Rightarrow \mathrm{q}_2=\frac{12 \times 5}{3}=20 \mu \mathrm{C}\end{aligned}\)
More questions from Physics
- An electron of mass \(m\) and a photon have same energy \(E.\) The ratio of de-Broglie wavelengths associated with them isJEE Mains 2021 Medium
- The circuit shown below is working as a \(8\; \mathrm{V}\;dc\) regulated voltage source. When \(12 \;\mathrm{V}\) is used as input, the power dissipated (in \(\mathrm{mW}\) ) in each diode is (considering both zener diodes are identical)
JEE Mains 2020 Medium - A source of sound \(A\) emitting waves of frequency \(1800\,Hz\) is falling towards ground with a terminal speed \(v.\) The observer \(B\) on the ground directly beneath the source receives waves of frequency \(2150\,Hz.\) The source \(A\) receives waves, reflected from ground of frequency nearly ..... \(Hz\) (Speed of sound \(= 343\,m/s\) )JEE Mains 2014 Easy
- The two wires \(A\) and \(B\) of equal cross-section but of different materials are joined together. The ratio of Young's modulus of wire \(A\) and wire \(B\) is \(20/11\). When the joined wire is kept under certain tension the elongations in the wires \(A\) and \(B\) are equal. If the length of wire \(A\) is \(2.2\) m, then the length of wire \(B\) is _______ m.JEE Mains 2026 Medium
- The maximum intensity in a Young's double slit experiment is \(I_0\). Distance between the slits (\(d\)) is \(5\lambda\), where \(\lambda\) is the wavelength of light used. The intensity of the fringe, exactly opposite to one of the slits on the screen, placed at \(D = 10d\) is _______.JEE Mains 2026 Hard
- A car of mass ' \(m\) ' moves on a banked road having radius ' \(r\) ' and banking angle \(\theta\). To avoid slipping from banked road, the maximum permissible speed of the car is \(v_0\). The coefficient of friction \(\mu\) between the wheels of the car and the banked road isJEE Mains 2025 Medium
More PYQs from JEE Mains
- A screw gauge has \(50\) divisions on its circular scale. The circular scale is \(4\) units ahead of the pitch scale marking, prior to use. Upon one complete rotation of the circular scale, a displacement of \(0.5\, mm\) is noticed on the pitch scale. The nature of zero error involved, and the least count of the screw gauge, are respectivelyJEE Mains 2020 Medium
- Consider a planet in some solar system which has a mass double the mass of earth and density equal to the average density of earth. If the weight of an object on earth is \({W}\), then weight of the same object on that planet will beJEE Mains 2021 Medium
- A bicycle tyre is filled with air having pressure of \(270\,kPa\) at \(27^{\circ}\,C\). The approximate pressure of the air in the tyre when the temperature increases to \(36^{\circ}\,C\) is \(............kPa\)JEE Mains 2023 Easy
- A printed page is pressed by a glass of water. The refractive index of the glass and water is \(1.5\) and \(1.33\), respectively. If the thickness of the bottom of glass is \(1\, cm\) and depth of water is \(5\, cm\) , how much the page will appear to be shifted if viewed from the top ?JEE Mains 2013 Medium