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Saturday, 31 October

JEE Main 2022 · PhysicsMultiple choiceSingle correctMediumApplication

JEE Main 28 June 2022, Shift 1, Physics Q39

Question 39 of 90 in this shift, Physics question 9 of 30, Section A.

The three charges q/2, q and q/2 are placed at the corners A, B and C of a square of side 'a' as shown in figure. The magnitude of electric field (E) at the corner D of the square, is :

The figure, in words

A square with corners labelled A (top left), D (top right), B (bottom left), C (bottom right). Charge labels inside the square near the corners: q/2 near A, q near B, q/2 near C; no label near D.
  1. (1)q4π∈0a2(12+12)\frac{q}{4\pi \in_0 a^2}\left(\frac{1}{\sqrt{2}}+\frac{1}{2}\right)Official answer
  2. (2)q4π∈0a2(1+12)\frac{q}{4\pi \in_0 a^2}\left(1+\frac{1}{\sqrt{2}}\right)
  3. (3)q4π∈0a2(1−12)\frac{q}{4\pi \in_0 a^2}\left(1-\frac{1}{\sqrt{2}}\right)
  4. (4)q4π∈0a2(12−12)\frac{q}{4\pi \in_0 a^2}\left(\frac{1}{\sqrt{2}}-\frac{1}{2}\right)

Official answer

Option 1

NTA final key.

Chapter
Electric Charges and Fields
Topic
Electric Field
Idea tested
Superposition Principle for Electric Fields

Same idea in other shifts

Asked 6× in all
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  2. 13 Apr 2023, Shift 1 · Q54A thin infinite sheet charge and an infinite line charge of respective charge densities +σ+\sigma and +λ+\lambda are placed parallel at 5…MediumNumerical value
  3. 28 Jun 2022, Shift 1 · Q38Given below are two statements : Statement-I : A point charge is brought in an electric field. The value of electric field at a point near…MediumTwo statements
  4. 28 Jun 2022, Shift 2 · Q40Two point charges A and B of magnitude +8×10−6+8\times10^{-6} C and −8×10−6-8\times10^{-6} C respectively are placed at a distance d apart. The…EasySingle correct
  5. 8 Jan 2020, Shift 1 · Q10Three charged particles A, B and C with charges −4q-4q, 2q2q and −2q-2q are present on the circumference of a circle of radius d. The…MediumSingle correctHas a figure

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. This question needs a figure we do not reproduce; it is described in words above. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.