why will in half life radioactive decay the quantity will decay to half regardless of how big or small the original quantity was?

Question

Suppose In first half-life radioactive decay radioactive atoms decay half their amount/quantity in a specific amount of time then in the second half-life why does it not decay according to its original quantity or in the same amount it decayed before ?

i mean why does it become half and then Half of the Half? and in the same amount of time it took before with the larger quantity?

Answer 1

The half-life is the time needed for half of a radioactive substance to decay.

An example, we start with 100 gm. of a radioactive substance. After 1 half-life 50 gm. decay leaving 50 gm. The next half-life is the time for half of this 50 gm to decay. After the second half life 25 gm remain. After the third, 12.5 gm; after the fourth 6.25; and so on......

 

Good?

Answer 2

It is an inherent basic property of the exponential function that the amount of change is proportional to the current amount, at any given time (because the rate of change is constant).

 

This is true whether it's exponential decay or exponential growth. A study of their graphs illustrates this.