CLASS 10 · LEARNING KNOWLEDGE
Exponential functions and half-life
How it works
Exponential functions describe constant relative changes. With halving, half remains after each half-life. With doublings, the initial value is multiplied by a power of two.
Note
N(t) = N₀·q^t; after n half-lives: N = N₀ / 2^n.
N(t) = N₀·q^t; after n half-lives: N = N₀ / 2^n.
An example
A substance amount of 880 mg halves every 7 hours. How much remains after 21 hours? Give the result in mg.
Number of half-lives=21:7=3. Remaining=880:2^3. Result: 110 mg.
Try it yourself now
50 Exercises · three difficulty levels · selection and number input
To the learning unit →Own explanation and own practice exercises by AmyMath. Subject reference framework: KMK Educational Standards Mathematics ESA/MSA. The topic assignment may vary by federal state.