11. quantity which can be measured PHYSICAL QUANTITIES Derived quantities Basic quantities
12. quantity which cannot be derived from any physical quantities Basic quantities cd candela Luminous Intensity mol mole N Amount of substance A ampere I Electric current K kelvin T/ Temperature s second t Time kg kilogram m Mass m metre l Length Symbol SI Unit Symbol Quantity
13. quantity which can be measured quantity which cannot be derived from any physical quantities PHYSICAL QUANTITIES Derived quantities Basic quantities
14.
15. quantity which can be measured quantity which cannot be derived from any physical quantities - eg : ? quantity which can be expressed in term of base quantity - eg : ? PHYSICAL QUANTITIES Derived quantities Basic quantities
17. for presenting larger and smaller values Unit prefixes p 10 12 pico n 10 9 nano 10 6 micro m 10 3 milli c 10 2 centi d 10 1 deci k 10 3 kilo M 10 6 mega G 10 9 giga T 10 12 tera Symbol Multiple Prefix
23. Real-world implications One example of the importance of agreed units is the failure of the NASA Mars Climate Orbiter , which was accidentally destroyed on a mission to the planet Mars in September 1999 instead of entering orbit , due to miscommunications about the value of forces: different computer programs used different units of measurement ( newton versus pound force ). Enormous amounts of effort, time, and money were wasted
24. Real-world implications On April 15, 1999 Korean Air cargo flight 6316 from Shanghai to Seoul was lost due to the crew confusing tower instructions (in metres) and altimeter readings (in feet). Three crew and five people on the ground were killed. Thirty seven were injured.
25. Real-world implications In 1983, a Boeing 767 (which came to be know as the Gimli Glider ) ran out of fuel in mid-flight because of two mistakes in figuring the fuel supply of Air Canada 's first aircraft to use metric measurements.This accident is apparently the result of confusion both due to the simultaneous use of metric & Imperial measures as well as mass & volume measures.