THE PRACTICE STUDIO
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PRACTICE / Exponential change and logarithms
Use the slope to find a halving time
For a decaying quantity N, a plot of ln(N/N₀) vertically against time in seconds has slope −0.20 s⁻¹.
Find the time for N to become N₀/2.
Organize the givens & assumptions
- Vertical axis: ln(N/N₀)
- Slope: −0.20 s⁻¹
- Target fraction: 1/2
Exact exponential decay and natural logarithm. The ratio N/N₀ is dimensionless.
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- B
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- D
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