A sample contanining a radioactive isotope prduces 2000 counts per minutes in a Giege counter. Afte 120hours, the sample produces 250 counts per minutes. What is the half-life of the isotope?

The activity of a radioactive isotope is 3000 count per minute at a certai time and 2736 count per minute after 48 h later. The half-life of this isotope is

A counter gives a count of 320 counts/minute for a radioactive source . After 75 minutes, the counter shows a count rate of 40 counts/minute . What is the half life period of the source ?

A counter rate metre is used to measure the activity of a radioactive sample. At a certain instant, the count rate was recorded as 400 counters per minute. Five minutes later, the count recorded was 200 counts per min. Calculate the decay and half-period of the sample.

A counter rate metre is used to measure the activity of a radioactive sample. At a certain instant, the count rate was recorded as 400 counters per minute. Five minutes later, the count recorded was 200 counts per min. Calculate the decay and half-period of the sample.

A count rate meter shows a count of 240 per minute from a given radioactive source. One hour later the meter shows a count rate of 30 per minute. The half-life of the source is.

A count rate meter shows a count of 240 per minute from a given radioactive source. One hour later the meter shows a count rate of 30 per minute. The half-life of the source is

For a radioactive sample, 15/16 th part decays in 20 minutes. The half-life of the sample is

A counter rate meter is used ot measure the activity of radioactive sample. At a certain instant the count rate was recorded as 475 counters per minute. Five minutes later, the count rate recorded was 270 counts per minute. Calculate the decay constant and half life period of the sample.