| ⇦ | 
| ⇨ |
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 maximum kinetic energy of emitted electrons in a photoelectric effect
- A nucleus at rest splits into two nuclear parts having radii in the ratio 1:2.
- A solid sphere, a hollow sphere and a ring are released from top of an inclined
- Imagine a new planet having the same density as that of earth but it is 3 times bigger
- Three resistances P,Q,R each of 2Ω and an unknown resistances S form the four arms
Topics: Atoms and Nuclei
(136)
Subject: Physics
(2479)
Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score
- The maximum kinetic energy of emitted electrons in a photoelectric effect
- A nucleus at rest splits into two nuclear parts having radii in the ratio 1:2.
- A solid sphere, a hollow sphere and a ring are released from top of an inclined
- Imagine a new planet having the same density as that of earth but it is 3 times bigger
- Three resistances P,Q,R each of 2Ω and an unknown resistances S form the four arms
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