3.2 Radioactivity and radiation

• Natuurkunde
• Middelbare school
• havo
• Leerjaar 3

Which radiation is the most harmful and which is the least harmful?

1. UV-radiation and gammaradiation
2. Gammaradiation and radiowaves
3. X-rays and radiowaves
4. Gammaradiation and microwaves

Blueprint of an atom

Isotopes

Same atomnumber

Different mass

(for example C-14 is NOT 
stable)

What happens when an atom is not stable?

It changes state.

1. Alpha

2. Bèta

3. Gamma

How many particles do you think decayed at Chernobyl?

Activity - Becquerel(bq)

Every time we measure particle decay in a second we call it 1 Bq

Chance and half-life

The chance a isotope decays is 50% on average. 

Some isotopes take 8 days to decrease in activity. Some 1 year. 

Some a million years

And some take even 4,5 billion years to decrease in activity by 50%. 

If the half-life of an isotope is 15 days. How active is it after 60 days?

1. 50%
2. 25%
3. 12,5%
4. 6,25%

Exercises

Complete from 3.2: 27, 30, 32, 33, 35, 37, 40, 42, 45, 46