NEET UG 2018 · Physics · Question 13
NEET 2018 Physics, question 13
Question 13 of the NEET 2018 paper (code AA) is a Physics question from Nuclei. Its idea, Fraction Decayed vs Fraction Remaining, was asked only this once in NEET 2017–2026. The CBSE official answer key gives option 3.
Updated 2026-10-08
Q13 · Physics
For a radioactive material, half-life is 10 minutes. If initially there are 600 number of nuclei, the time taken (in minutes) for the disintegration of 450 nuclei is
- 130
- 210
- 320Official answer
- 415
Official answer: option 3 · CBSE official answer key
Same idea
The only question on Fraction Decayed vs Fraction Remaining
No other NEET paper from 2017–2026 tested this exact idea.
Fraction Decayed vs Fraction Remaining: every question and how it was framed
The chapter
Nuclei in ten years of NEET
13 questions from 2017–2026, asked in 9 of 10 papers, about 1.2 a paper. Radioactive Decay alone had 9.