GENERAL KNOWLEDGE

Detailed explanation-1: -Exponential decay of radioactive species at which decay rate at a certain time is involved. i.e., activity is proportional to the number of undecayed nuclei.

Detailed explanation-2: -Radioactivity is the emission of -or, -particles and -rays due to the disintegration of the nuclei of atoms. The rate of disintegration is proportional to the number of atoms at any point in time and the constant of proportionality is called the radioactivity decay constant.

Detailed explanation-3: -The greater the decay constant, the greater the activity of the sample. The activity depends on the number of undecayed nuclei remaining in the sample. The minus sign indicates that the number of nuclei remaining decreases with time-however, for calculations it can be omitted.

Detailed explanation-4: -Using the decay equation to find the number of nuclei remaining. You can use the decay equation N = N0e-t to find the value of N for any value of t if you’re given and the number of undecayed nuclei you start off with, N0.

Detailed explanation-5: -One of the applications of radioactive decay is radioactive dating, in which the age of a material is determined by the amount of radioactive decay that occurs. The rate of decay is called the activity R: R=Nt. The SI unit for R is the becquerel (Bq), defined by 1Bq=1decay/s.