Electrostatic Potential and Capacitance

CBSE Class 12 Physics · every board question from this chapter, 2023–2026 · 28 of them repeated across years

• In a region, the electric potential varies as V=10-50 x, where V is in volts and x in meters. The electric field in the region is:2026
• Three point charges 2q, -2q and q are kept at the vertices of an equilateral triangle of side l. The potential energy of the…2026
• In a region electric field is given by E=4 x i N / C. The potential difference between points A(x=1 m) and B(x=3 m),(V A-V B) is2026
• Three point charges +q,-2 q and +q are placed along x -axis at points x=-1 m, x=0 m and x=2 m respectively. The potential energy…2026
• Two metal spheres of radii r 1 and r 2( r 1) having charges q 1 and q 2 respectively kept in air, are brought in contact. Which…2026asked 3×
• The figure represents the variation of the electric potential V at a point in a region of space as a function of its position…2026
• A conducting wire connects two charged metallic spheres A and B of radii r 1 and r 2 respectively. The distance between the…2026asked 3×
• The electric potential for various points in x -y plane is given by V=1.0 x^2 -2.0 y^2, where V is in volts and x, y are in…2026
• An electric dipole with dipole moment P=(2 · 54 × 10^-28 C. m)(2 · 00 i+3 · 00 j) is placed in an electric field E=(1000 ( N)/ )…2026
• Two points R and S are equidistant from two charges + Q and - 2Q. The work done in moving a charge - Q from point R to S is:2026
• A point charge of 5 μ C is located at (1 cm, 1 cm) in x -y plane. A second charge of 6 μ C is brought from infinity to point (-3…2026
• Two parallel plate capacitors X and Y are connected in series to a 6 V battery. They have the same plate area and same plate…2026asked 2×
• A parallel plate capacitor of capacitance C has a dielectric slab between its plates. It is charged to a potential difference V…2026
• An electric field E=E 0 i exists in a region of space. Draw three equipotential surfaces in the region. Two point charges -q and…2026
• (i) Draw electric field lines and equipotential surfaces for a system of two equal and opposite point charges separated by some…2026
• A 12.0 μ F capacitor is charged to a potential difference of 150 V. The terminals of the charged capacitor are then connected to…2026
• A parallel plate capacitor of capacitance C is charged to V volt by a battery. After sometime the battery is disconnected and the…2026
• Draw electric field lines and equipotential surfaces for a system of two equal positive charges separated by some distance. Using…2026
• The electric potential (V) and electric field (E) are closely related concepts in electrostatics. The electric field is a vector…2026asked 3×
• Capacitors are manufactured with certain standard capacitances and working voltages. However, these standard values may not be…2026asked 3×
• (i) In the figure, OA and OB show the variation of electric potential V at a point due to two point charges Q 1 and Q 2 with…2026asked 3×
• Derive an expression for the capacitance of a parallel plate capacitor of plate area A and plate separation d with air present…2026asked 3×
• (i) Explain the following statements giving reason: (I) An equipotential surface through a point is normal to the electric field…2026asked 3×
• A metal sheet is inserted between the plates of a parallel plate capacitor of capacitance C. If the sheet partly occupies the…2025asked 2×
• In the circuit shown, the charge on the left plate of 20 μ F capacitor is -50 μ C. The charge on the right plate of the 12 μ F…2025
• The electric field (E) and electric potential (V) at a point inside a charged hollow metallic sphere are respectively:2025
• Two horizontal plates, separated by 1 cm, are arranged one above the other. A particle of mass 5 mg and charge 2 nC is released…2025
• In the figure curved lines represent equipotential surfaces. A charge Q is moved along different paths A, B, C and D. The work…2025
• The effective capacitance of the network between points A and B shown in the figure is:2025
• Four point charges Q each, are held at the four corners of a square of side l. The amount of work done in bringing a charge Q…2025
• "There is a limit to the amount of charge that can be stored on a given capacitor." Explain. A capacitor is charged by a battery…2025
• A parallel plate capacitor has plate area A and plate separation d. Half of the space between the plates is filled with a…2025
• A capacitor of plate area A and plate separation d is charged by a battery to voltage V. The battery is disconnected and plates…2025
• Two point charges of -5 μ C and 2 μ C are located in free space at ( -4 cm, 0 ) and ( 6 cm, 0 ) respectively. Calculate the…2025
• A parallel plate capacitor consists of two conducting plates kept generally parallel to each other at a distance. When the…2025asked 3×
• A capacitor is a system of two conductors separated by an insulator. In practice, the two conductors have charges Q and -Q with…2025asked 2×
• A parallel plate capacitor has two parallel plates which are separated by an insulating medium like air, mica, etc. When the…2025asked 3×
• (i) A parallel plate capacitor with plate area A and plate separation d has a capacitance C 0. A slab of dielectric constant K…2025asked 3×
• (i) Two point charges 5 μ C and -1 μ C are placed at points ( -3 cm, 0,0) and ( 3 cm, 0,0 ) respectively. An external electric…2025asked 3×
• The plates P 1 and P 2 of a 2 μ F capacitor are at potentials 25 V and -25 V respectively. The charge on plate P 1 will be:2024
• An isolated conductor, with a cavity, has a net charge +Q. A point charge +q is inside the cavity. The charges on the cavity wall…2024
• Two charges +q each are kept ' 2 a ' distance apart. A third charge -2 q is placed midway between them. The potential energy of…2024
• The capacitance of a parallel plate capacitor having a medium of dielectric constant K=4 in between the plates is C. If this…2024
• Consider a group of charges q 1, q 2, q 3 … such that Σ q ≠ 0. Then equipotentials at a large distance, due to this group are…2024
• A proton is taken from point P 1 to point P 2, both located in an electric field. The potentials at points P 1 and P 2 are -5 V…2024asked 3×
• Ten capacitors, each of capacitance 1 μ F, are connected in parallel to a source of 100 V. The total energy stored in the system…2024
• A proton and an alpha particle having equal velocities approach a target nucleus. They come momentarily to rest and then reverse…2024asked 3×
• A proton of energy 1.6 MeV approaches a gold nucleus ( Z=79 ). Find the distance of its closest approach.2024
• An air-filled parallel plate capacitor with plate separation 1 mm has a capacitance of 20 pF. It is charged to 4.0 μ C. Calculate…2024
• Three point charges Q 1, Q 2 and Q 3 are located in x-y plane at points (-d, 0),(0,0) and (d, 0) respectively. Q 1 and Q 3 are…2024
• A thin spherical conducting shell of radius R has a charge q. A point charge Q is placed at the centre of the shell. Find (i) the…2024
• The electric field in a region is given by E=(10 x+4) i where x is in m and E is in N/C. Calculate the amount of work done in…2024
• Two conducting spherical shells A and B of radii R and 2 R are kept far apart and charged to the same charge density σ. They are…2024
• The figure shows four pairs of parallel identical conducting plates, separated by the same distance 2.0 cm and arranged…2024asked 3×
• Dielectrics play an important role in design of capacitors. The molecules of a dielectric may be polar or non-polar. When a…2024asked 3×
• (i) Derive an expression for potential energy of an electric dipole p in an external uniform electric field E. When is the…2024asked 3×
• (i) Obtain an expression for the electric potential due to a small dipole of dipole moment p, at a point r from its centre, for…2024asked 3×
• (i) Draw equipotential surfaces for an electric dipole. (ii) Two point charges q 1 and q 2 are located at r 1 and r 2…2024asked 3×
• (i) Obtain the expression for the capacitance of a parallel plate capacitor with a dielectric medium between its plates. (ii) A…2024asked 2×
• (i) Obtain the expression for the capacitance of a parallel plate capacitor with a dielectric medium between its plates. (ii) A…2024
• (i) A dielectric slab of dielectric constant ' K ' and thickness ' t ' is inserted between plates of a parallel plate capacitor…2024asked 3×
• Two charges q 1 and q 2 are placed at the centres of two spherical conducting shells of radius r 1 and r 2 respectively. The…2023
• A point charge q 0 is moving along a circular path of radius a, with a point charge -Q at the centre of the circle. The kinetic…2023
• The capacitors, each of 4 μ F are to be connected in such a way that the effective capacitance of the combination is 6 μ F. This…2023asked 3×
• Assertion: Work done in moving a charge around a closed path, in an electric field is always zero. Reason (R): Electrostatic…2023asked 3×
• Three point charges Q, q and -q are kept at the vertices of an equilateral triangle of side L as shown in figure. What is (i) the…2023
• Obtain an expression for electrostatic potential energy of a system of three charges q, 2 q and -3 q placed at the vertices of an…2023asked 3×
• Two charged conducting spheres of radii a and b are connected to each other by a wire. Find the ratio of the electric fields at…2023asked 3×
• Three point charges Q 1(-15 μ C), Q 2(10 μ C) and Q 3(16 μ C) are located at (0 cm, 0 cm),(0 cm, 3 cm) and (4 cm, 3 cm)…2023
• A 100 μ F capacitor is charged by a 12 V battery. How much electrostatic energy is stored by the capacitor? The capacitor is…2023
• A capacitor is a system of two conductors separated by an insulator. The two conductors have equal and opposite charges with a…2023asked 3×

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