Title 02. ELECTROSTATIC POTENTIAL AND CAPACITANCE(H).pdf ✅

NEET REVISION 02. ELECTROSTATIC POTENTIAL AND CAPACITANCE(H) NEET REVISION Date: March 18, 2025 Dura on: 1:00:00 Total Marks: 180 INSTRUCTIONS INSTRUCTIONS PHYSICS 1. The potential of a large liquid drop when eight liquid drops are combined is . Then the po‐ tential of each single drop was [Q359416] (1) (2) (3) (4) 2. When charge of is shifted from infinity to a point in an electric field, it is found that work done by electrostatic forces is . If the charge is doubled and taken again from infinity to the same point without accelerating it, then find the amount of work done by electric field and against electric field. [Q359511] (1) (2) (3) (4) 3. Find equivalent Capacitance between point and if Capacitance between any two plates is . [Q359311] (1) (2) (3) (4) 4. Equipotential surfaces are shown in figure. Then the electric field strength will be [Q359536] (1) along - axis (2) along - axis (3) at an angle with - axis (4) at angle with - axis 5. The electric potential in a region is represented as . Obtain expression for the electric field strength. [Q359549] (1) (2) (3) (4) 6. The electric field potential at a point in the space region depends only on coordinates as . Find the space charge density [Q359354] (1) (2) (3) (4) 7. In absence of dielectric medium, capacity of a parallel plate capacitor is . A sheet of dielec‐ tric constant and thickness of one third of the plate separation is inserted between the plates. If new capacity is , then: [Q359195] (1) (2) (3) (4) 8. The magnitude of work done in placing four charges at the corners of a square of side as shown in the figure, will be [Q359470] (1) (2) (3) (4) 20 V 10 V 7.5 V 5 V 2.5 V 10μC −10μJ −10μJ −20μJ −30μJ −40μJ A B C C n + 1 C 2n + 1 C 2n − 1 C n − 1 100 V m−1 X 100 V m−1 Y 200 V m−1 120 ∘ X 50 V m−1 120 ∘ X V = 2x + 3y − z 2 ^i + 3 ^j − k^ −2 ^i − 3 ^j + k^ −3i + 2j + 3k^ 3 ^i + 2 ^j − 3k^ x V = −ax 3 + b ρ(x) 4aε0x 6aε0x aε0x 2aε0x C0 k C = C C0 3k 2k + 1 = C C0 2k 3k + 1 = C C0 3k + 1 2k = C C0 2k + 1 3k a (−4 + √2) kq 2 a (4 + √2) kq 2 a (4 − √2) kq 2 a 2 (4 + √2) kq 2 a 2
NEET REVISION 9. Find the heat produced in the circuit, shown in the figure, on closing the switch . [Q358982] (1) (2) (3) (4) 10. Consider a conducting spherical shell of radius . A charge is given onto the surface of the sphere. The total energy of the shell is [Q359492] (1) (2) (3) (4) 11. A charged particle is shot with speed to‐ wards another fixed charged particle . It ap‐ proaches upto a closest distance and then re‐ turns. If were given a speed , the closest dis‐ tance of approach would be [Q359469] (1) (2) (3) (4) 12. Figure shows a solid hemisphere with a charge of distributed uniformly through its vol‐ ume. The hemisphere lies on a plane and point is located on the plane, along a radial line from the centre of curvature at distance . The electric potential at point due to the hemi‐ sphere, is [Q359405] (1) (2) (3) (4) 13. The space between the plates of a parallel plate capacitor is filled with ‘dielectric’ whose ‘di‐ electric constant’ varies with distance as per the relation : = a constant ) The capacitance , of this capacitor, would be related to its ‘vacuum’ capacitance as per the relation ( is the separation between the plates) [Q359228] (1) (2) (3) (4) 14. If an electron enters into a space between the plates of a parallel plate capacitor at an angle with the plates and leaves at angle to the plates. The ratio of its kinetic energy while enter‐ ing the capacitor to that while leaving will be: [Q359086] (1) (2) (3) (4) 15. A parallel plate capacitor is connected to a bat‐ tery. The plates are pulled apart with a uniform speed . If is the separation between the plates, the time rate of change of electrostatic energy of capacitor is proportional to : [Q359087] (1) (2) (3) (4) 16. In figure a system of four capacitors connected across a 10 battery is shown. Charge that will flow from switch when it is closed is: [Q358991] (1) from to (2) from to (3) Zero (4) from to 17. A combination of parallel plate capacitors is maintained at a certain potential difference. When a 3 thick slab is introduced between all the plates, in order to maintain the same po‐ tential difference, the distance between plates in increased by 2.4 . Find the dielectric con‐ stant of the slab. [Q359186] (1) 6 (2) 4 (3) 3 (4) 5 18. If 1000 droplets each of potential and ra‐ dius are combined to form a big drop. Then, the potential of the drop as compared to small droplets will be [Q359396] (1) (2) (3) (4) 19. Find out energy stored in an imaginary cubical volume of side in front of a infinitely large non-conducting sheet of uniform charge density . [Q359452] S 2μJ 4μJ 0μJ 3μJ R Q Q2 4πε0 Q2 4πε0R Q2 8πε0R Q2 πε0R q v Q Q r q 2v r 2r r/2 r/4 5 nC P 15 cm P 150 V 300 V 450 V 600 V a K(x) = Ko + λx (λ C C0 d C = C0 λ dln(1+K0/λd) C = C0 λ dln(1+K0λd) C = C0 λd ln(1+K0λd) C = C0 λd ln(1+λd/K0) α β [ ] 2 cos β cos α [ ] 2 sin β sin α [ ] 2 cos α cos β [ ] 2 sin α sin β u x x x −2 x −1 x 2 V S 5 μC b a 20 μC a b 5 μC a b mm mm 1 V r 1000 V 800 V 100 V 20 V a σ

NEET REVISION (1) (2) (3) (4) 29. A capacitor of charged upto is connected in parallel with another capacitor of , which is charged upto . The com‐ mon potential is [Q358988] (1) (2) (3) (4) 30. A parallel plate capacitor of area , plate sepa‐ ration and capacitance is filled with three different dielectric material having dielectric constants and as shown. If a single dielectric material is to be used to have the same capacitance in this capacitor, then its dielectric constant is given by [Q359188] (1) (2) (3) (4) 31. If a capacitor has plate area and distance between plates is . Now a dielectric of dielec‐ tric constant is placed between capacitor as shown in figure. Find new capacitance : [Q359189] (1) (2) (3) (4) 32. A parallel plate capacitor is made of two square plates of side , separated by a distance . The lower triangular portion is filled with a dielectric constant , as shown in the fig‐ ure. Capacitance of this capacitor is [Q359171] (1) (2) (3) (4) 33. Assertion : A point charge is placed at centre of spherical cavity inside a spherical conductor as shown. Another point charge is placed outside the conductor as shown. Now as the point charge is pushed away from conductor, the potential dif‐ ference between two points and within the cavity of sphere remains constant. Reason : The electric field due to charges on outer surface of conductor and outside the conductor is zero at all points inside the conductor. [Q359431] (1) Both Assertion and Reason are correct and Reason is the correct ex- planation of the Assertion. (2) Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion. (3) Assertion is correct but Reason is incorrect. (4) Assertion is incorrect but reason is correct. 34. The work done against electric forces in in‐ creasing the potential difference of a condenser from to is . The work done in in‐ creasing its potential difference from to will be [Q359101] (1) (2) (3) (4) 35. Charge distribution on a ring in plane is shown in the figure. Then electric potential at origin is [Q359362] (1) (2) Zero (3) (4) 36. The potential (in volts) of a charge distribution is given by for for does not depend on and . If this potential is generated by a constant charge per unit volume (in units of ) which is spread over certain region, then choose the correct statement. [Q359356] (1) in the en- tire region. (2) in the en- tire region. 24 N 28 N 6√5 N 4√35N 20 μF 500 V 10 μF 200 V 250 V 300 V 400 V 600 V A d C K1, K2 K3 C k K = K1 + K2 + 2K3 K = + 2K3 K1K2 K1+K2 K = + K1K3 K1+K3 K2K3 K2+K3 = + + 1 K 1 K1 1 K2 1 2K3 C0 A ‘d ′ ‘k ′ 4kC0 (k+3) 3kC0 (k+4) (k+3)C0 4k 3kC0 (k+4) a d (d << a) K 1 2 Kε0a 2 d ln K Kε0a 2 d(K−1) Kε0a 2 2d(K+1) ln K Kε0a 2 d q Q Q (VA − VB) A B 20 V 40 V W 40 V 50 V 4 W 3W 4 2W W 2 x − y Q 4πε0r Q 2πε0r 3Q 4πε0r V (z) = 30 − 5z 2 |z| ≤ 1 m V (z) = 35 − 10|z| |z| ≥ 1m V (z) x y ρo, εo ρo = 40εo ρo = 20εo