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QNEET-2023-Ph-250: NEET 2023 Physics - Class 12 NEET-2023-Ph-250 Solution: The half life of a radioactive substance is 20 minutes. In how…
The half life of a radioactive substance is 20 minutes. In how much time the activity of substance drops to th of its initial value? 40 minutes 60 minutes 80 minutes 20 minutes
Multiple Choice Options
- A 40 minutes
- B 60 minutes
- C 80 minutes
- D 20 minutes
Step-by-Step Verified Solution
Half life T = 20 min
Left fraction of activity 1 16
_ R R 0 = ( 1 2 ) t / T 1 16 = ( 1 2 ) t / 20 ( 1 2 ) 4 = ( 1 2 ) t / 20 4 = t 20 t = 80 min