JEE Main 3 August 2021, Shift 2, Physics Q21

Question 21 of 90 in this shift, Physics question 21 of 30, Section B.

\underline{\hspace{2em}}\times10^{-10}

J (joule) energy is contained in a 120 m length of a laser beam operating at 4mW.

Official answer

NTA final key.

Chapter: Electromagnetic Waves
Topic: No close match in our taxonomy
Idea tested: No close match in our taxonomy

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 42 of the 174 JEE Main shifts held from 2017 to 2026.