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 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 the 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

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 count rate meter is used to measure that activity of a given amount of a radio active element. At one instant, the meter shows 475 counts/minute. Exactly 5 minutes later, is shown 270 counts/minute then Half life of the sample is (in minute)

The count rate meter is used to measure that activity of a given amount of a radio active element. At one instant, the meter shows 475 counts/minute. Exactly 5 minutes later, is shown 270 counts/minute then Half life of the sample is (in minute)

A pure radio-chemical preparation was observed to disintegrate at the rate of 2140 counts/minutes at 12.35 P.M. of the same day, the disintegration rate of the sample was only 535 count/minutes. What is the half-life of the material?

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.

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.