1. Prefixes and Units Shatin Tsung Tsin Secondary School By Mr. C.K. Yu

2. Physical Quantities and Units Physical quantities Symbol Unit Unit symbol TimetSeconds Distance/ Displacement smetrem Speed / Velocityvmetre per second m s -1 Acceleration ( 加速度 ) ametre per second square m s - 2

3. Physical Quantities and Units Physical quantities Symbol Unit Unit symbol Frequencyf Hertz ( 赫茲 ) Hz Mass ( 質量 ) mKilogramkg WeightWNewtonN

4. Metric Prefixes NameSymbolMeaningNameSymbol Meaning TeraT10 12 Decid 10 -1 GigaG10 9 Centic 10 -2 MegaM10 6 Millim 10 -3 Kilok10 3 Micro µ 10 -6 Nanon 10 -9 Picop 10 -12 Are there any prefixes larger than Tera or smaller than pico? web-site : http://physics.nist.gov/cuu/Units/prefixes.html

5. Unit conversion Convert 1 km h -1 to unit of m s -1. 1 km = 1000 m and 1 hour = 3600 s

6. Unit conversion Convert 10 m min -1 to unit of km h -1. 1 km = 1000m  and 1 hour = 60 min.  So 10 m min -1 = 0.6 km h -1

7. Practice Convert the following into the specified units 300 m s -1 =km h -1 50 km h -1 =m s -1 400 m min -1 =m s -1 4200 J o C -1 =kJ o C -1 1000 kg m -3 =g mm -3 1 080 13.9 6.67 4.20 0.001

8. The End Thank you very much