| ⇦ | 
| ⇨ |
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: - CO₂ laser uses
- The energy released in the fission of 1 kg of ₉₂U²³⁵ is (energy per fission = 200 MeV)
- A particle of mass 1 mg has the same wavelength as an electron moving with a velocity
- Two planets at mean distances d₁ and d₂ from the sun have their frequencies n₁ and n₂
- A tyre filled with air (27° C and 2 atm) bursts. The temperature of air is (ˠ=1.5)
Topics: Atoms and Nuclei
(136)
Subject: Physics
(2479)
Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score
- CO₂ laser uses
- The energy released in the fission of 1 kg of ₉₂U²³⁵ is (energy per fission = 200 MeV)
- A particle of mass 1 mg has the same wavelength as an electron moving with a velocity
- Two planets at mean distances d₁ and d₂ from the sun have their frequencies n₁ and n₂
- A tyre filled with air (27° C and 2 atm) bursts. The temperature of air is (ˠ=1.5)
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