half life?

Dear student,

The halflife is the amount of time it takes for half of the atoms in a sample to decay. The halflife for a given isotope is always the same; it doesn't depend on how many atoms you have or on how long they've been sitting around.

Half-life of a substance is the time in which the substance gets decomposed to half its original volume. It is usually used with radioactive substances. This is because it is very difficult to determine their full life . Therefore, the time in which thwy decompose is calculated by using their half-life. For eg., 

(1) The half life of U-238 is 4.47 billion years. This means that it will get reduced to half its present volume in 4.47 billion years.

(2) The half life of C-14 is 5568 years, give or take 30 years ( plus-minus 30 years ). This, again means that C-14 will decompose to half its present volume in about 5568 years.

Please Approve!!!!