Physics-
General
Easy
Question
The count rate of 10g of radioactive material was measured at different times and this has been shown in the figure. The half life of material and the total counts (approximately) in the first half life period, respectively are
- 4h, 9000
- 3h, 14000
- 3h, 235
- 3h, 50
The correct answer is: 3h, 14000
Read time for 50 count rate, it gives half life period of 3 hrs, one small square gives 600 counts (10 × 60). The number of small squares between graph and time axis are approx 24
Hence count rate = 
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