| ⇦ | 
| ⇨ |
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: - A ball is dropped from the root of a tower of height h
- A bar magnet of moment of inertia I is vibrated in a magnetic field of induction
- The reddish appearance of the sun at sunrise and sunset is due to
- A person wants a real image of his own, 3 times enlarged. Where should he stand
- The voltage of clouds is 4×10⁶ volt with respect to ground. In a lightening
Topics: Atoms and Nuclei
(136)
Subject: Physics
(2479)
Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score
- A ball is dropped from the root of a tower of height h
- A bar magnet of moment of inertia I is vibrated in a magnetic field of induction
- The reddish appearance of the sun at sunrise and sunset is due to
- A person wants a real image of his own, 3 times enlarged. Where should he stand
- The voltage of clouds is 4×10⁶ volt with respect to ground. In a lightening
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