Learn

Saturday, 31 October

JEE Main 2021 · PhysicsMultiple choiceSingle correctMediumCalculation

JEE Main 26 February 2021, Shift 1, Physics Q13

Question 13 of 90 in this shift, Physics question 13 of 30, Section A. NTA dropped this question from the final key; it is left out of every count on this site.

Consider the combination of 2 capacitors C1\mathrm{C_1} and C2\mathrm{C_2}, with C2>C1\mathrm{C_2}>\mathrm{C_1}, when connected in parallel, the equivalent capacitance is 154\frac{15}{4} times the equivalent capacitance of the same connected in series. Calculate the ratio of capacitors, C2C1\frac{\mathrm{C_2}}{\mathrm{C_1}}.
  1. (1)2915\frac{29}{15}
  2. (2)1511\frac{15}{11}
  3. (3)154\frac{15}{4}
  4. (4)11180\frac{111}{80}

Official answer

Dropped by NTA (marks given to all)

NTA final key: NTA final key 'D' = question dropped.

Chapter
Electrostatic Potential and Capacitance
Topic
Parallel Plate Capacitors
Idea tested
Series and Parallel Combinations

Same idea in other shifts

Asked 17× in all
  1. 4 Apr 2026, Shift 2 · Q37From the circuit given below, the capacitance between terminals AA and BB shown in the circuit is ________ μ\muF. (take…MediumDiagram basedHas a figure
  2. 5 Apr 2024, Shift 1 · Q54Three capacitors of capacitances 25 μF25\ \mu\mathrm{F}, 30 μF30\ \mu\mathrm{F} and 45 μF45\ \mu\mathrm{F} are connected in parallel to a supply of…MediumNumerical value
  3. 9 Apr 2024, Shift 1 · Q40A capacitor is made of a flat plate of area A and a second plate having a stair-like structure as shown in figure. If the area of each…MediumSingle correctHas a figure
  4. 6 Apr 2023, Shift 2 · Q59As shown in the figure, two parallel plate capacitors having equal plate area of 200 cm2^2 are joined in such a way that a≠ba \neq b. The…MediumNumerical valueHas a figure
  5. 10 Apr 2023, Shift 1 · Q41The equivalent capacitance of the combination shown isMediumDiagram basedHas a figure
  6. 11 Apr 2023, Shift 2 · Q60In the given circuit, C1=2 μF,C2=0.2 μF,C3=2 μF,C4=4 μF,C5=2 μF,C6=2 μF\mathrm{C_1 = 2\ \mu F, C_2 = 0.2\ \mu F, C_3 = 2\ \mu F, C_4 = 4\ \mu F, C_5 = 2\ \mu F, C_6 = 2\ \mu F}, The…HardNumerical valueHas a figure
  7. 15 Apr 2023, Shift 1 · Q55In the given figure the total charge stored in the combination of capacitors is 100 μ\muC. The value of 'xx' is ______________.EasyNumerical valueHas a figure
  8. 26 Jul 2022, Shift 1 · Q41The total charge on the system of capacitors C1=1 μC_1 = 1\ \muF, C2=2 μC_2 = 2\ \muF, C3=4 μC_3 = 4\ \muF and C4=3 μC_4 = 3\ \muF connected in parallel…EasySingle correct

Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.