Which is a good example of a contact force? A. protons in the nucleus of an atom B. a ball falling down after it's thrown up int
1 answer:
You might be interested in
These 2 isotopes are all of bromine that is naturally found (their percentages add up to 100%). In order to calculate the mean atomic mass, we can use the following calculation: 
. This yields an average atomic mass of 79.903 amu. This procedure is general; whenever we have many types F of a specific genre G, the mean of the genre G can be calculated by:
where
is the proportion of type i in the genre G. In this example, Br79 and Br81 are the 2 types and the genre is Bromine.
where