A Radioactive Source Has a Half-Life of 2 Min $\times$ 10⁶
B)1

question 87

Multiple Choice

A radioactive source has a half-life of 2 min.At time t = 0 it is placed near a detector and the counting rate is observed to be 3000 counts/s.If the detection efficiency is 25%,how many radioactive nuclei are there at time t = 0?

• A)1.04 \(\times\) 10⁶
• B)1.67 \(\times\) 10⁶
• C)2.08 \(\times\) 10⁶
• D)3.41 \(\times\) 10⁶
• E)3.79 \(\times\) 10⁶

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Definitions:

Behavioral Genetics

The study of the role of genetic and environmental factors in shaping behaviors and personality.

Heritability Coefficient

Heritability coefficient is a statistical estimate that indicates how much of the variation in a particular trait within a population can be attributed to genetic differences among individuals.

Twin Studies

Research studies that compare the similarities and differences between monozygotic (identical) and dizygotic (fraternal) twins to understand genetic and environmental influences on traits.

Personality Traits

Enduring characteristics or patterns of behavior that define an individual's responses across various situations.