Units and Dimensons Flashcards
How many base quantities are there?
There are 7 base quantities
What are the base quantities?
Length
Mass
Time
Temperature
Elastic Current
Luminous Intensity
Amount of Substance \
What is a dimension?
It is the basic quantity (Like length)
What is dimension and Si Unit of Length?
L
Metre (m)
What is dimension and Si Unit of Mass
M
Kilogram (Kg)
What is dimension and Si Unit of Time
T
Seconds (s)
What is dimension and Si Unit of Temperature
K
Kelvin (K)
What is dimension and Si Unit of Electric Current
I
Ampere (A)
What is dimension and Si Unit of Luminous Intensity
J
Candela (cd)
What is dimension and Si Unit of Amount of Substance
N
mol (Moles)
What is dimension and Si Unit of Time
T
Time (s)
What are derived quantities?
Quantities that you get by multiplying the same or different base units
What are the derived units?
Area
Speed
Density
Force
What are the dimensions and Si unit of Area
L^2
m^2
What are the dimensions and Si unit of Speed
LT^-1
ms^-1
What are the dimensions and Si unit of Density
ML^-3
kg m^-3
What are the dimensions and Si unit of Force
MLT^-2
kg m s^-2
How much is a kilo
1000
10^3
How much is a Tera
1 TB= 10^12
How much is a milli
1mm= 10^-3
How much is a micro
1 us= 10^-6
What is the rule of adding/subtracting quantities?
They must be of the same dimension and unit, if it isnt the same unit then standardize the units (Making them the same)
What is the rule when multiplying/dividing quantities?
You can multiply quantities even if they have different dimensions however a new quantity is created with a new name
What are dimensionless quantities
Quantities with no units. eg (Strain)
What is dimensional analysis?
Checking if each quantity in an equation has the same dimensions, if they do not then the equation is not correct. It acts as an initial check.
What is 1 litre to cm?
1000cm^3
Is this equation dimensionally correct?
-Force= density x area x velocity
-pressure = height × gravity acceleration × density
-power = speed × force
-energy = mass × (speed)2
How to convert from Hours to Second
Multiply by 60 to get minutes then multiply again to get seconds
How to convert from M to cm to mm
From M to cm you multiply by 100
From cm to mm multiply by 10
How to convert between m/s to km/h
