Question

8. Carbon-14 (C.) decays at a constant rate in such a way that it reduces to 50% in 5,568 years. Find the age
of an old wooden piece in which the carbon is only 25% of the original.​

Answer 1

the carbon 14 (C

14

) reduces to 50% in 5568 days then,

it will reduce to 25% in ⇒(5568×2) days

further it will reduce 12.5% in ⇒(5568×3)

days = 16,704 days

Answer 2

Let the concentration of carbon be x.

Time taken to decay to x/2 (half of x) is 5568 years.

Again time taken to decay from x/2 to x/4 is 5568 years. (because decay rate is constant)

25% of original means, from x to x/4

Time taken to decay from x to x/4 = 5568 + 5568

= 11136 years.

Hope, this helps you.