⇦ | ⇨ |
The half life of radium is about 1600 year. Of 100 gram of radium existing now, 25g will remain unchanged after
Options
(a) 4800 year
(b) 6400 year
(c) 2400 year
(d) 3200 year
Correct Answer:
3200 year
Explanation:
100 gram at beginning, I = 0
25 gram remains undecayed.
N / N₀ = (1 / 2)ⁿ ⇒ 25 / 100 = (1 / 2)ⁿ
⇒ 1 / 4 = (1 / 2)ⁿ
Therefore, n = 2
Time = n × T
= 2 × 1600
= 3200 years.
Related Questions: - A drum of radius R and mass M, rolls down without slipping along an inclined plane
- If critical angle for a material to air passage is 30°, the refractive index
- A body starts from rest with an acceleration of 2 m/s². After 5 second,
- A bucket full of water is revolved in a vertical circle of 2m
- A tuning fork vibrates with 2 beats in 0.04 second. The frequency of the fork is
Topics: Radioactivity
(83)
Subject: Physics
(2479)
Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score
- A drum of radius R and mass M, rolls down without slipping along an inclined plane
- If critical angle for a material to air passage is 30°, the refractive index
- A body starts from rest with an acceleration of 2 m/s². After 5 second,
- A bucket full of water is revolved in a vertical circle of 2m
- A tuning fork vibrates with 2 beats in 0.04 second. The frequency of the fork is
Topics: Radioactivity (83)
Subject: Physics (2479)
Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score
18000+ students are using NEETLab to improve their score. What about you?
Solve Previous Year MCQs, Mock Tests, Topicwise Practice Tests, Identify Weak Topics, Formula Flash cards and much more is available in NEETLab Android App to improve your NEET score.
Share this page with your friends
Leave a Reply