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Physical quantities and units - Coggle Diagram
Physical quantities and units
physical quantities
including
Base quantities
Electric current
Temperature
Time
Amount of substance
Length
Luminous intensity
Mass
Derived quantities
Velocity
Acceleration
Density
Force
Volume
Energy
Area
Charge
Pressure
Power
Resistance
is a
feature of something that can be measured
express as a
Numerical value (magnitude)
Unit
Measurement
Significant figures
Each measurement have infinite number of significant figures
Power of the are not significant figures
Trailing zeros after decimal places
If the measurement is less than one, then all zeros occuring to the left of last non-zero digit are not significant
Zeros between two non-zero digits
Trailing zeros in a number without a decimal point are not significant
Non-zero digits
Chasing measurement of quantity doesn't change the number of significant figures
Errors
2 types
Systematic errors
Due to
Zero error
Parallax
Calibration
Instrument faults
affects
Accuracy
Random errors
Due to
Unpredictable variations
affects
Precision
Uncertainty
Percentage uncertainty
Single measurement
Fractional uncertainty
Repeated measurement
Absolute uncertainty
Combining uncertainities
Mutiplication/division
Powers
Addition/subtraction
Si Units
For
Checking homogeneity of equations
has
Prefixes
including
Centi
Milli
Deci
Micro
Kilo
Nano
Mega
Pico
Giga
Tera
is a
Standardization
Has 2 parts
Si Base Units
Coherent Derived Units
Scalars and vectors
2 types
Vectors
Defined by
Magnitude and direction
Scalars
Defined by
Magnitude only