WAEC - Physics (1994 - No. 28)
In 24 days a radioactive isotope decreases in mass from 64g to 2g. What is the half life of the radioactive material
0.75 days
2.58 days
4 days
4.80 days
6 days
คำอธิบาย
64g → 32g → 16g → 8g → 4g → 2g
Half life time= 24/5 = 4.8 days
Half life time= 24/5 = 4.8 days