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प्रश्न
Half life of a certain radioactive material is 8 hours.
If one starts with 600 g of this substance, how much of it will disintegrate in one day?
उत्तर
Since the half-life is 8 hours, therefore, the mass of radioactive material left after 8 hours = `600/2 = 300"g"`
∴ After another 8 hours, mass left = `300/2 = 150"g"`
Similarly, after another 8 hours mass left = `150/2 = 75 "g"`
After one day 75 g of the substance will remain.
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