| ⇦ |
| ⇨ |
The half life of a radioactive isotope ‘X’ is 20 years. It decays to another element ‘Y’ which is stable. The two elements ‘X’ and ‘Y’ were found to be in the ratio of 1 : 7 in a sample of a the given rock. The age of the rock is estimated to be
Options
(a) 60 years
(b) 80 years
(c) 100 years
(d) 40 years
Correct Answer:
60 years
Explanation:
The value of x is 1/8
= x₀/8 = x₀/2³ ⇒ t = 3t = 3 x 20 = 60 yrs
Hence the estimated age of rock is 60 yrs.
Related Questions: - A Carnot engine, having an efficiency of η=1/10 as heat engine, is used
- Two thin lenses of focal lengths f₁ and f₂ are in contact and coaxial.
- When a p-n junction is reverse biased, then the current through the junction
- Three solids of masses m₁,m₂ and m₃ are connected with weightless string
- Electromagnets are made of soft iron because soft iron has
Topics: Atoms and Nuclei
(136)
Subject: Physics
(2479)
Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score
- A Carnot engine, having an efficiency of η=1/10 as heat engine, is used
- Two thin lenses of focal lengths f₁ and f₂ are in contact and coaxial.
- When a p-n junction is reverse biased, then the current through the junction
- Three solids of masses m₁,m₂ and m₃ are connected with weightless string
- Electromagnets are made of soft iron because soft iron has
Topics: Atoms and Nuclei (136)
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