Question
Question: Suppose a radioactive substance disintegrates completely in 10 days. Each day it disintegrates at a ...
Suppose a radioactive substance disintegrates completely in 10 days. Each day it disintegrates at a rate which is twice the rate of the previous day. The percentage of the material left to be disintegrated after passing of 9 days is-
A
10
B
20
C
25
D
50
Answer
50
Explanation
Solution
On the last day we have 100% decay i.e. on the ninth day 50% decay must be there or 50% must be left.