Appendix D — Units and Order of Magnitude
| Multiplication factor | Prefix | Symbol | Example |
|---|---|---|---|
| 1012 = 1,000,000,000,000 | Tera | T | 1 Terawatt = 1 TW = 1 x 1012 watts |
| 109 = 1,000,000,000 | Giga | G | 1 Gigabyte = 1GB = 1 x 109 bytes |
| 106 = 1,000,000 | Mega | M | 1 Megapascal = 1 MPa = 1 x 106 Pascals |
| 103 = 1,000 | kilo | k | 1 kilonewton = 1 kN = 1 x 103 Newtons |
| 10-3 = 0.001 | milli | m | 1 millisecond = 1 ms = 1 x 10-3 seconds |
| 10-6 = 0.000001 | micro | µ | 1 micrometer = 1 µm = 1 x 10-6 meters |
| 10-9 = 0.000000001 | nano | n | 1 nanovolt = 1 nV = 1 x 10-9 Volts |
| 10-12 = 0.000000000001 | pico | p | 1 picoamp = 1 pA = 1 x 10-12 Amps |
| Quantity | SI Unit (symbol) | US Unit (symbol) | Conversion factor |
|---|---|---|---|
| 1st Moment of Area (Q) | meters3 (m3) | inches3 (in.3) | 1 in.3 = 1.639 x 10-5 m3 |
| 2nd Moment of Area (I) | meters4 (m4) | inches4 (in.4) | 1 in.4 = 4.162 x 10-7 m4 |
| Area (A) | meters2 (m2) | inches2 (in.2) | 1 in.2 = 6.452 x 10-4 m3 |
| Force (F) | Newton (N) | Pound (lb) | 1 lb = 4.448 N |
| Length (L) | Meter (m) | Foot (ft) or Inch (in.) | 1 ft = 12 in. = 0.3048 m |
| Moment of a force (M) | Newton-meter (N·m) | Pound-inch (lb·in.) | 1 lb·in. = 0.1130 N·m |
| Power (P) | Watt (W) | horsepower (hp) or lb·ft/s | 1 hp = 550 lb·ft/s = 1.356 W |
| Pressure (P) | Pascal (Pa) | Pound per square inch (psi) | 1 psi = 6895 Pa |
| Strain (ε) | Unitless | Unitless | - |
| Stress (σ) | Pascal (Pa) = N/m2 | Pound per square inch (psi) = lb/in.2 | 1 psi = 6895 Pa |
| Time (t) | Second (s) | Second (s) | - |
| Torque (T) | Newton-meter (N·m) | Pound-inch (lb·in.) | 1 lb·in. = 0.1130 N·m |