Practice question · Multiple choice
Radioactive decay and Newton's law of cooling produce the same differential equation with different meanings. What do the two systems have in common?
Hints
- Write both laws as .
- Compare what sits in the brackets.
Show the answer
C. That the rate is proportional to the amount or the gap
Why
A differential equation describes a structure, not a substance. This is why the same mathematics serves nuclear physics, thermodynamics and compound interest, the proportionality is what they have in common.
Practise Differential models in one variable
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