| ⇦ | 
| ⇨ |
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: - If the focal length of a concave mirror is 50 cm, then where should the object
- A block of mass 4 kg is kept on a rough horizontal surface.The coefficient of static
- In a diffraction pattern due to a singleslit of width a, the first minimum is observed
- A cycle wheel of radius 4 m completes one revolution in two seconds. Then acceleration
- The near point and far point of a person are 40 cm and 250 cm, respectively.
Topics: Radioactivity
(83)
Subject: Physics
(2479)
Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score
- If the focal length of a concave mirror is 50 cm, then where should the object
- A block of mass 4 kg is kept on a rough horizontal surface.The coefficient of static
- In a diffraction pattern due to a singleslit of width a, the first minimum is observed
- A cycle wheel of radius 4 m completes one revolution in two seconds. Then acceleration
- The near point and far point of a person are 40 cm and 250 cm, respectively.
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