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

Question

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

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 value, after how many days will it be safe to enter the room?
A. 100 days
B. 1000 days
C. 300 days
D. 10 days.

Monjur Alahi

4 views

2025-01-04 04:42

1 Answers

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Salim Ahmed Kawsar · Accepted Answer · 2023-02-05T15:29:48+06:00

Salim Ahmed Kawsar

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`
`=99.6 ~~ 100` days.

4 views Answered 2023-02-05 15:29