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How do I find how much radioactive material is left after time t if I know its half-life?

To answer this question, all you have to know is that the amount of material as a function of time, M(t), is related to the decay constant, λ, by the equation M(t) = M 0 exp(-tλ), where M 0 is the amount of ...
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Answered by Wilf S. • Physics tutor
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What are the advantages and disadvantages of using postal questionnaires as a research method?

Advantages of using a postal questionnaire include the fact that it is not as time consuming as an interview. Questionnaires can be designed to be quick and easy for the respondant to complete. It can also b...
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Answered by Isobel W. • Sociology tutor
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How to analyse the win of Donald Trump in election from the view of communication theory?

the information on main newspapers and websites showed that Hillary would win the election. it seems like the final result was out of all people's expection. but actually the win of Donald Trump represents p...
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How do Functionalist and Marxist perceptions of the family differ?

Functionalists view the family and its contribution to society as positive, whereas Marxits see it as a negative institution. Functionalists see the nuclear family as essential for social order. They view it...
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Answered by Isobel W. • Sociology tutor
33415 Views

Can you explain what the flux of a light source is?

The word 'flux' can be used in many different contexts, but in general it refers to the amount of 'stuff' passing through a unit area of space per unit time. In the case of light sources, we can measure flux...
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Answered by Wilf S. • Physics tutor
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