L.2 Flashcards
What is the MKS system of units?
- metre
- kilogram
- second
What is the ampere unit for?
- electrical current
What is the kelvin unit for?
- temperature
What is the mole unit for?
- substance quantity
What is the candela unit for?
- luminous intensity
What are the fundamental quantities that make up dimensions?
- length (L)
- time (T)
- mass (M)
- temperature (0)
- charge (Q)
Are dimensions different from units? Why?
- yes.
- the same dimension can be expressed in different units for example 150 m and 2 miles bc they both have the same dimension of length. But we cannot add 3 m and 10 seconds because they have different dimensions
How can we use dimensions to aid understanding?
- we can use it to check simple formula or mathematical expressions to see if they are dimensionally correct
- if both the right and left hand side have the same dimensions , we did everything right
What is an exponent?
- the number of 0’s.
- 10 = 10^1 , 100 = 10^2 , 1000 = 10^3
For instance: light is 300,000,000 m/s
So the scientific notation of that would be: 3 x 10^8 m/s
How would 0.001 and 0.00024 be expressed in scientific notation?
- 0.001 = 10^-3
- 0.00024 = 2.4 x 10^-4
What happens when scientific notations are multiplied?
- the exponents are added together
- example: 10^4 • 10^2 = 10^(4+2) = 10^6
Or
(2 x 10^3) • (6 x 10^5)
= (2 x 6) • (10^3+5)
= 12 • 10^8
= 1.2 • 10^9
What happens to the exponents of scientific notation if they are divided?
- exponents are subtracted from each other.
- example:
10^5/10^2 = 10^5-2 = 10^3
Or
(9 x 10^5) / (3 x 10^7)
= (9/3) • 10^5-7
= 3 • 10^-2
What is the prefix and symbol of 10^12
Prefix: Tera
Symbol: T
What is the prefix and symbol of 10^9
Prefix: giga
Symbol: G
What is the prefix and symbol of 10^6
Prefix: mega
Symbol: M