| ⇦ |
| ⇨ |
A radio isotope X with a half life 1.4 x 10⁹ years decays to Y which is stable. A sample of the rock from a cave was found to contain X and Y in the ratio 1:7. The age of the rock is
Options
(a) 1.96 x 10⁹ years
(b) 3.92 x 10⁹ years
(c) 4.20 x 10⁹ years
(d) 8.40 x 10⁹ years
Correct Answer:
4.20 x 10⁹ years
Explanation:
No explanation available. Be the first to write the explanation for this question by commenting below.
Related Questions: - The wavelength λₑ of an electron and λₚ of a photon are of same energy E are related by
- If 10000 V is applied across an X-ray tube, what will be the ratio of de-Broglie
- How much work is required to carry a 6 μC charge from the negative terminal
- In a uniform circular motion, work done in one complete rotation is
- A series combination of n₁ capacitors, each of value C₁, is charged by a source
Topics: Atoms and Nuclei
(136)
Subject: Physics
(2479)
Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score
- The wavelength λₑ of an electron and λₚ of a photon are of same energy E are related by
- If 10000 V is applied across an X-ray tube, what will be the ratio of de-Broglie
- How much work is required to carry a 6 μC charge from the negative terminal
- In a uniform circular motion, work done in one complete rotation is
- A series combination of n₁ capacitors, each of value C₁, is charged by a source
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

X/Y=1/7
Y=7X
Let the initial atoms be N.
Then,
X+Y=N
X+7X=N
8X=N
X=N/8
Hence, the final atoms be N/8.
N/8/N=(1/2)^n
(1/8)^3=(1/2)^n
n=3
Then, t=n×T1/2
t=3×1.4×10^9
t=4.2×10^9