A radioactive element has half-life period of 30 days. How much of it will be left after 90 days?
A. `13.5%`
B. `46.5%`
C. `87.5%`
D. `90.15%`
1 Answers
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The half-life period of a radioactive element is `1.4 xx 10^(10)` years. Calculate the time in which the activity of the element is reduced to 90% of
`t_(1//2) = 0.693/k or k=0.693/t_(//2)= 0.693/(1.4 xx 10^(10)`years `t=2.303/k log N_(0)/N_(t) = 2.303/(0.693 // 1.4 xx 10^(10) years) xx log 100/90` `= 2.303/0.693 xx 1.4 xx 10^(10) xx 0.4558` years...
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A radioactive element gets spilled over the floor of a room. Its half life period is 30 days. If its initial activity is ten times the permissible val
Correct Answer - A a) Let the initial activity for safe working = A `therefore` Initial activity `[A]_(0) = 10 A` `k=0.693/30` days `t=(2.303)/t log ([A]_(0))/([A])` `t=(2.303 xx (30"days"))/(0.693) log 10`...
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2 Answers 1 views
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2 Answers 4 views
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