Suppose that Polonium decays at a rate propotional to the amount present. If a sample of...

Suppose that Polonium decays at a rate propotional to the amount present. If a sample of

Polonium -210 decays so that there is 50 gr left after 140 days and 25 gr after 280 days, how much Polonium

did the sample have to begin with?

A balloon is rising at a constant speed 4 m/sec. A boy is cycling along a straight road at a speed

of 8 m/sec. When he passes under the balloon, it is 36 metres above him. How fast is the distance between

the boy and balloon increasing 3 seconds later?

Expert Solution

milcah answered 2 years ago

1) A radioactive substance decays at a rate proportional to the amount of the substance at...

1) A radioactive substance decays at a rate proportional to the amount of the substance at present time. Initially 200 grams of a the substance was present and remain 80% of the initial amount after 2 hours. A.) Determine the amount of the substance remaining after 10 hours (counted in grams) B.) Determine the time that 60% of the initial amount of the substance has decayed (counted in hours)

Consider the production series of radioactive sample A decays to sample B then decays to stable...

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After a patient consumes a medication, the amount of drug that remains in the body decays...

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Polonium-218 is an alpha emitter with a half-life of 3.0 minutes. **)If a sample contains 55...

Polonium-218 is an alpha emitter with a half-life of 3.0 minutes. **)If a sample contains 55 mg of Po−218 (atomic mass = 218.008965 amu), how many alpha emissions would occur in 27.0 minutes? **)If the polonium were ingested by a person, to what dose of radiation (in Ci) would the person be exposed? (I need correct answer for this please)

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A radioactive material disintegrates at a rate proportional to the amount currently present. If Q(t) is...

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The body removes antibacterial drugs at a rate in proportion to the amount present. Your task...

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Suppose you randomly sample 64 cans and find the mean amount of Coke in this sample...

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Suppose the interest rate is 10.1% APR with monthly compounding.What is the present value of...

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14.) Suppose that the present annual inflation rate is 3.2% and you project that this will...

14.) Suppose that the present annual inflation rate is 3.2% and you project that this will be the maintained. Recall that the inflation rate is the amount a typical collection of primary goods and services will increase in price each year. This is defined by the national government. How many years will it take for the overall level of prices to be 1.75 times what the level is now? (Hint: This a compound interest situation. You will need to use...

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