A half-life is the amount of time it takes for half of the radioactive atoms in a sample to decay into a more stable form. It is a characteristic property of a specific radioactive isotope.
The half-life of a radioactive isotope can be determined through experimentation and measurement. Scientists use specialized equipment to measure the rate of decay and calculate the time it takes for half of the atoms to decay.
The fission barrier is the energy barrier that must be overcome in order for a nucleus to undergo nuclear fission. The height of the fission barrier determines the stability of the nucleus, with higher barriers indicating a more stable nucleus.
No, the half-life of a radioactive isotope is a constant value for that particular isotope and cannot be changed. It is a fundamental property of the isotope.
Radiometric dating uses the known half-life of a radioactive isotope to determine the age of a sample. By measuring the ratio of the original isotope to its decay product, scientists can calculate how many half-lives have passed and therefore the age of the sample.