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प्रश्न
The half-life of radium is 1550 years. Calculate its disintegration constant (`lambda`) .
उत्तर
`T_"1/2" = 1550 "years"`
⇒ `("In" 2)/lambda = 1550 xx 365 xx 24 xx 3600 "second"`
⇒ `lambda = ("In" 2)/(1550 xx 365 xx 24 xx 3600) "s"^-1= 0.693/(1500 xx 3.1536 xx 10^7)`
⇒ `lambda = 1.418 xx 10^-11 "disintegration/second"`
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