Science Academy
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Activity Calculator

☢ Nuclear & Decay. Use the Activity formula to find activity, decay constant λ, nuclei: pick the value you want, type the others, and the answer updates as you go.

A=λNA = \lambda N
Activity138.6 Bq

Pick the ○ next to the value you want to find, fill in the others, and it solves as you type.

What each letter means

QuantityUnit
ActivityBq
Decay constant λ1/s
Nucleino unit

Worked example

Find the activity when Decay constant λ = 0.1386 1/s, Nuclei = 1000.

Using A = λ N: Activity = 138.6 Bq.

Frequently asked questions

What is the formula for Activity?

A = λ N.

What do the letters stand for, and what units are used?

Activity in Bq, Decay constant λ in 1/s, Nuclei.

How do you calculate activity?

Put the values into A = λ N. For example, with Decay constant λ = 0.1386 1/s, Nuclei = 1000, activity = 138.6 Bq.

Can I solve for a different value?

Yes. In the calculator above, pick the circle next to any value (activity, decay constant λ, nuclei) and fill in the others: it rearranges the formula for you.

All chemistry formulas in the Chemistry Formulas