Home
Class 12
PHYSICS
20% of a radioactive substances decay in...

20% of a radioactive substances decay in 10 days . Calculate the amount of the original material left after 30 days.

A

0.512

B

0.628

C

0.15

D

0.2127

Text Solution

Verified by Experts

The correct Answer is:
A
Fraction of the substance left
= f`= 1 - 20/100` = 0.8
Let `t_(1)` = 10 day , `t_(2)` = 30 day
fraction , n =`t_(2)/t_(1)=(30)/(10)=3`
but `N/N_(0)= (f)^(n) = (0.8)^(3)`
`N/N_(0) xx 100 = 0.512 xx 100`
`=51.25%`
Promotional Banner

Topper's Solved these Questions

  • NULECUS

    BITSAT GUIDE|Exercise BITSAT Archives|8 Videos

  • MAGNETIC FIELD

    BITSAT GUIDE|Exercise All Questions|52 Videos

  • PHYSICS FOR GASEOUS STATE

    BITSAT GUIDE|Exercise BITSAT Archives|8 Videos

Similar Questions

Explore conceptually related problems

If 10% of a radioactive material decays in 5 days, then the amount of original material left after 20 days is approximately.

Half-life of a radioactive substance is 2.9 days. Calculate the amount of 10 mg of substance left after 29 days.

If 20% of a radioactive sample decays in 10 days, then the amount of substance left after 20 days will be approximately

A radioactive substance has decay constant of 0.231 "day"^(-1) . Calculate the percentage of the substance left after 6 days.

The half-life of a radioactive substance is 10 days. This means that

A radioactive material has half-life of 10 days. What fraction of the material would remain after 30 days ?

Starting with 1.0g of a radioactive sample, 0.25 g fo its is left after 5 days. Calculate the amount which was left one day.

The half life period of a radioactive substance is 10 year. The amount of the substance decayed after 40 years would be

If 10% of a radioactive substance decays in every 5 year, then the percentage of the substance that will have decaed in 20 years will be .

A radioative substance decays 10% in 5 days. The aamount remains after 20 days is [log 3 =0.4771]