ACT Preparation / Unit 21 ACT 2002 short lesson, about 20 seconds
Hypothesis and Theory
Captions available
The idea
A hypothesis is a tentative explanation awaiting tests. A theory is a tested and confirmed explanation for observations.
In practice
The claim that a new fertilizer helps tomatoes is a hypothesis until tested; an explanation confirmed again and again across many studies is a theory.
Where people slip
Everyday speech uses theory to mean a guess; science does not.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Builds on
Unlocks
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