Question

A radioactive material has a half-life of 8 years. The activity of the material will decrease to about 1/8 of its original value in-

• A. 256 year
• B. 128 year
• C. 64 year
• D. 24 year

Answer 1

Answer: (D)

24 year

Answer 2

T_1/2 = 8 years ; A.P = $\frac { 1 } { 8 }$= (n = 3)

t = n T_1/2 = 3 × 8 = 24 years