The half-life of a radioactive substance is $10$ days. This means that
- the substance completely disintegrates in 20 days
- the substance completely disintegrates in 40 days
- 1/8 part of the mass of the substance will be left intact at the end of 40 days
- 7/8 part of the mass of the substance disintegrates in 30 days
The Correct Option is D
Solution and Explanation
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- Transcription
Concepts Used:
Decay Rate
The disintegration of unstable heavy atomic nuclei into lighter, more stable, atomic nuclei, accompanied in the process by the emission of ionizing radiation (alpha particles, beta particles or gamma rays). This is a random process at the atomic level but, given a large number of similar atoms, the decay rate on average is predictable, and is usually measured by the half-life of the substance.
The equation for finding out the decay rate is given below:
