Answer:
40 N/m
Explanation:
The diagram attached is used to answer the question
We know from Hooke's law that extension is directly proportional to the applied force hence
F=kx where x is extension, F is applied force and k is the spring constant. Making k the subject of the formula then
From the attached diagram extension is given by subtracting unstretched spring from stretched spring hence extension, x=1-0.5=0.5m
Substituting 20 N for F and 0.5 m for x then
From the activity values and the decay constant, the mass of of Strontium in the sample is:
The decay constant of an element is the probability of decay of a nucleus per unit time.
{λ = ln 2 / t1/2
where;
t1/2 is the half-life of the isotope.
The half-life is converted to seconds since the decay constant is asked in per seconds.
Hence;
The activity of the element, A, the decay constant, λ and the number of nuclei, N are related as follows:
Molar mass of Strontium-90 is 90 g.
1 mole of Strontium-90 contains 6.02×10^23 nuclei.
The mass, m of Strontium in the sample is calculated:
Therefore, the mass of of Strontium in the sample is:
Learn more about decay constant at: brainly.com/question/17159453