there are 500g of cobalt to 60 that has a half life of 5years ,how many grams of cobalt are remained after 15years
Three half lives
500 * 1/2 * 1/2 * 1/2
= 500/8 grams
To find out how many grams of cobalt are remained after 15 years, we need to calculate the amount of radioactive material left using the half-life formula.
The half-life formula for radioactive decay is given by: A = A₀ * (1/2)^(t / T), where A₀ is the initial amount, A is the final amount, t is the time passed, and T is the half-life.
In this case, the initial amount of cobalt is 500 grams, the half-life is 5 years, and the time passed is 15 years. We can substitute these values into the formula and calculate the final amount.
A = 500 * (1/2)^(15/5)
A = 500 * (1/2)^3
A = 500 * (1/8)
A = 62.5 grams
Therefore, after 15 years, there will be 62.5 grams of cobalt remaining.