1. amountremaing=original(e^(.692*time/hslf)
.1=1 e^ ( ) take ln of each side
ln(.1)=.692*100/halflife
halflife= you do it. I get about 30 days.
Two Questions:
1) A certain radioactive isotope has leaked into a small stream. 100 days later after the leak 10% of the original amount of the substance. Determine the half-life of this radioactive isotope.
2) During a research experiment, it was found that the number of bacteria in a culture at a rate proportional to its size. At 5am there were 3,000 bacteria present in the culture. At noon, the number of bacteria grew to 6,200. How many bacteria will be at midnight.
I have no idea how to do this! please help.
3 answers
2. find half life from 5am, noon counts as done above. Then, figure amount remaining from the same formula knowing noon count, and halflife.
im sorry but im still confuse i have 8 other problems that are similar to this. if you just show me how to do these, i can figure out the rest of my hw. please.how to find the halflife?