Introduction Flashcards
Law
A mathematical relation between variables inferred from the data or though some reasoning process.
Observational experiment
A scientist collects data that seem important.
Testing experiment
A specific hypothesis is “put on trial.”
Hypothesis
An idea that explains why or how something that you observe happens.
Prediction
A statement of what should happen in a particular experiment if the hypothesis being tested were true.
Assumption
A statement that is accepted without evidence.
Point-like object
A simplified representation of a real object. You can model a real object as a point-like object when:
(a) all of its parts move in the same way, or
(b) when the object is much smaller than the other relevant lengths in the situation.
Model
A simplified representation of an object, a system (a group of objects), an interaction, or a process.
Physical quantity
A feature or characteristics of a physical phenomenon that can be measured in some unit. A measuring instrument is used to make a quantitative comparison of this characteristic with a unit of measure.
Unit
A chosen standard.
SI system
International basic units of measurement. (See “SI Units” Deck)
Significant digits
Number of digits that carry meaning contributing to the precision of the result.
Rules of thumb:
• Non-zero digits & 0's in b/n --> sig.
• Leading 0's not sig.
• Trailing 0's
decimal: count them as sig.
no decimal: ambiguous–not sig.
Scientific notation
Writing numbers in terms of their power of 10.
Scalar quantities
Physical quantities that contain information about magnitude, and not direction.
Vector quantities
Physical quantities that contain information about magnitude and direction.
