If the radioactive decay constant of radium is 1.07 x 10^-4 per year, then its half-life period is approximately equal to:
Correct answer: B. 6,476 years
- A. 8,900 years
- B. 6,476 years
- C. 7,000 years
- D. 2,520 years
Explanation
The half-life of a radioactive element is given by the following formula: T1/2 = ln(2) / λ where T1/2 is the half-life, ln(2) is the natural logarithm of 2, and λ is the decay constant. In this case, the decay constant is given as 1.07 x 10-4 per year. So, the half-life of radium is: T1/2 = ln(2) / 1.07 x 10-4 = 6,476 years.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? [email protected]
About Half-life and Rate of Decay
Half-life is the time required for half the unstable nuclei in a sample to decay, and it remains constant for a particular radioactive nuclide. Questions use the exponential decay law, decay constant, activity, remaining quantity and mean life. Radioactive decay is random for individual nuclei but predictable for large samples.
Practise Nuclear Physics
1,254 free Nuclear Physics MCQs from Physics, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Physics questions like this
Physics is on 16 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
More Half-life and Rate of Decay questions
A radioactive decay rate of radioactive elements is found to be 103 disintegrations per sec at a certain time. If the half-life of the element is 1 second, the decay rate after one second is _ and after 3 second is _.
In a sample of radioactive material, what fraction of the material will decay after half of its half-life?
If the decay or disintegration constant of a radioactive substance is λ, then its half-life and mean life are respectively:
Half-life of radioactive element depends upon:
A radioactive substance has a half-life of 60 minutes. After 3 hours, the fraction of atoms that have decayed would be:
The Half-life of radium is 1600 years. Which of the following is the fraction of a sample of radium that would remain un-decayed after 6400 years?