Half Life Flashcards
1
Q
How do you measure half life on a graph?
A
Find the halfway point on the y-axis,
Draw a straight line over to the curve on the graph
Draw the line down to the x-axis
The number the line touches on the x-axis is the half life
2
Q
How do you calculate half life in this example?
Example:
The activity of a radioisotope is 640Bq. Two hours later it has fallen to 40Bq. Find the half life of this sample?
A
640/2 = 320 320/2 = 160 160/2 = 80 80/2 = 40
This ⬆️ shows it has been through four half lives. If two hours represents four half lives the 2/4 = 0.5. Each half life is 30 minutes
