MyQuestionIcon

1

You visited us 1 times! Enjoying our articles? Unlock Full Access!

Uses of Radioactive Substances

A radioactive...

Question

A radioactive substance decays 10% in 5 days. The amount remains after 20 days is what? [log 3 = 0.1771]

A

90%

No worries! We‘ve got your back. Try BYJU‘S free classes today!

B

81%

No worries! We‘ve got your back. Try BYJU‘S free classes today!

C

72%

No worries! We‘ve got your back. Try BYJU‘S free classes today!

D

60.61%

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

Open in App

Solution

The correct option is D 60.61%
using half rate formula
$\frac{5}{20} = l n x / 90$
$x = 90 \times 0.67$
$60.6$

Suggest Corrections

thumbs-up

0

Similar questions

20 %

of a radioactive substance decays in

5

days, then find the approximate percentage of the initial amount left after

20

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

Q. A sample of the radioactive substance is found 90% of its initial amount after on day. What % of the original sample can be found after 3 days?

Q. A radioactive substance decays from

100

6.25

100

days. What is the half-life of this radioactive substance?

Q. A radioactive substance decays to

\frac{1}{16^{t h}}

of its initial activity in 40 days. The half-life of the radioactive substance expressed in days is

View More

Join BYJU'S Learning Program

similar_icon

Related Videos

lock

Uses of Radioactive Substances

CHEMISTRY

Watch in App

explore_more_icon

Explore more

Uses of Radioactive Substances

Standard IX Chemistry

Join BYJU'S Learning Program

CrossIcon