1A sample is counted for 30 minutes, and yields 1220 counts. the background count rate for the detector is 5 cpm. a) what are the standard deviation of the gross and background count rates for a 30 min count time?
b)what is the net count rate and its standard deviation?
c)Define a 95% confidence interval for the net count rate ?
2) A detector shows a background count of 500 counts in 30 minute time. what would the LLD for this system be for counting time of:
3)How many counts should be collected in a sample in order to have a 1% error at 95% confidence level?
4) Radioactive sample is counted for 8 min and gives 2300 counts . calculate the count rate and standard deviation for the sample ?
5) Radioactive sample gives an average count of 9390Â±95 and the counting time for each count is 20Â±1 min, calculate the average count rate and its standard deviation.