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Saturday, 31 October

JEE Main 2021 · PhysicsMultiple choiceTwo statementsEasyConceptual

JEE Main 24 February 2021, Shift 1, Physics Q18

Question 18 of 90 in this shift, Physics question 18 of 30, Section A.

Given below are two statements : Statement I : Two photons having equal linear momenta have equal wavelengths. Statement II : If the wavelength of photon is decreased, then the momentum and energy of a photon will also decrease. In the light of the above statements, choose the correct answer from the options given below.
  1. (1)Both Statement I and Statement II are true
  2. (2)Both Statement I and Statement II are false
  3. (3)Statement I is true but Statement II is falseOfficial answer
  4. (4)Statement I is false but Statement II is true

Official answer

Option 3

NTA final key.

Chapter
Dual Nature of Radiation and Matter
Topic
Photoelectric Effect
Idea tested
Photon Energy and Momentum

Same idea in other shifts

Asked 5× in all
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  2. 2 Apr 2025, Shift 1 · Q44A monochromatic light is incident on a metallic plate having work function ϕ\phi. An electron, emitted normally to the plate from a point…MediumSingle correct
  3. 13 Apr 2023, Shift 2 · Q60An atom absorbs a photon of wavelength 500500 nm and emits another photon of wavelength 600600 nm. The net energy absorbed by the atom in…MediumNumerical value
  4. 27 Aug 2021, Shift 2 · Q53The number of photons emitted by a monochromatic (single frequency) infrared range finder of power 1 mW and wavelength of 1000 nm, in 0.1…EasyNumerical value

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.