| ⇦ | 
| ⇨ |
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: - Water rises in a vertical capillary tube up to a height of 2.0 cm.
- The periodic waves of intensities I₁ and I₂ pass through a region at the same time
- An air core solenoid has 1000 turns and is one meter long. Its cross sectional area
- In the Young’s double slit experiment, a point P on the central bright fringe
- Two closed organ pipes when sounded simultaneously give 4 beats/second.
Topics: Radioactivity
(83)
Subject: Physics
(2479)
Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score
- Water rises in a vertical capillary tube up to a height of 2.0 cm.
- The periodic waves of intensities I₁ and I₂ pass through a region at the same time
- An air core solenoid has 1000 turns and is one meter long. Its cross sectional area
- In the Young’s double slit experiment, a point P on the central bright fringe
- Two closed organ pipes when sounded simultaneously give 4 beats/second.
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