Unit 22.Atomic physics

04.21.2020
08:21:03
Dear students,today's topic in physics : radioactivity
Pg.no : 319 & 320
The important points are
1.there are two ways in which radioactive substance can cause us problems :
* If a radioactive substance gets inside us ; it's radiation can harm us - it's contaminated
* If the radiation they produce hits our body ,we say that we have received a dose of radiation.- it's irradiated
2.infact, we are exposed to low levels of radiation all the time - this is known as background radiation
3.in addition , we may be exposed to radiation from artificial sources.
Look at figure 2.23 - it gives clear idea about sources of background radiation and artificial radiation
No homework
For better understanding of concepts watch the below videos