| ⇦ | 
| ⇨ |
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: - If a wire is stretched to four times its length, then the specific resistance
- In old age arteries carrying blood in the human body become narrow resulting
- In a common emitter (CE) amplifier having a voltage gain G, the transistor
- Two similar springs P and Q have spring constants Kp and Kq, such that Kp>Kq.
- A pure semiconductor behaves slightly as a conductor at
Topics: Atoms and Nuclei
(136)
Subject: Physics
(2479)
Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score
- If a wire is stretched to four times its length, then the specific resistance
- In old age arteries carrying blood in the human body become narrow resulting
- In a common emitter (CE) amplifier having a voltage gain G, the transistor
- Two similar springs P and Q have spring constants Kp and Kq, such that Kp>Kq.
- A pure semiconductor behaves slightly as a conductor at
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