LEVEL 3 ENGINEERING PRINCIPLES - PREREQUISITES INFORMATION Metric Prefixes PREFIX
VALUE
STANDARD FORM
SYMBOL
Tera
1,000,000,000,000
1x1012
T
Giga
1,000,000,000
1x109
G
Mega
1,000,000
1x106
M
Kilo
1000
1x103
K
-
1
1
-
Milli
0.001
1x10-3
m
Micro
0.000 001
1x10-6
μ [Mu]
Nano
0.000 000 001
1x10-9
n
Pico
0.000 000 000 001
1x10-12
p
Engineering Examples: 1. 2. 3. 4.
150 MPa = 150,000,000 Pa 1,550 W = 1.55 KW 0.000 020 F = 20 μF 22,450 mm = 22.45 m
Rearranging and Solving Equations Fundamental Principles
1. ALL EQUATIONS have a left-hand side and a right-hand side, separated by an equals sign 2. Equations must remain balanced (the left-hand side MUST ALWAYS equal the right-hand side) 3. Any operation that is performed on the left-hand side of an equation MUST be performed on the right-hand side of the equation for it to remain balanced 4. To rearrange an equation for a given variable, ‘strip away’ all other numbers, terms and expressions, leaving the variable on its own (note: this can only be done by using the allowable operations below)
Allowable Operations (Rules)
1. You can add a number, term or expression to both sides of an equation 2. You can subtract a number, term or expression from both sides of an equation 3. You can multiply each side of the equation by the same number, term or expression 4. You can divide each side of the equation by the same number, term or expression 5. You can raise or lower each side of the equation by a given power (i.e. square / cube each side, or square root / cube root each side) 6. You can take reciprocals of both sides of the equation Note: there are a number of additional rules which will be covered in later topics. These are just the basics that are required to get started