Hoo Sze Yen
Physics SPM 2008
CHAPTER 1: INTRODUCTION TO PHYSICS
1.1 Understanding Physics
Physics: Study of all natural phenomenon Physics is a branch of science centred on the study of matter, energy, and the connection between them.
1.2
Physical Quantities
1.2.1 Quantities and Units
Physical quantities – quantities that can be measured Basic quantities – quantities that cannot be defined in any other form of physical quantities Derived quantities – combination of basic quantities via multiplication of division Units SI Units – standard size for comparison – internationally accepted units (determined in Paris in a meeting in 1960) – Le Systemé International d’Unites
The five basic quantities: Quantity 1. Length 2. Mass 3. Time 4. Temperature 5. Electric current
Symbol l m t T I
SI Units meter kilogram second kelvin ampere
Units (Symbol) m kg s K A
1.2.2 Scientific Notation (Standard Form)
A × 10n where A ≤ 1 < 10 and n = integer The value of A should always be rounded to 3 or 4 significant numbers.
Chapter 1: Introduction to Physics
Page 1 of 6
Hoo Sze Yen
Physics SPM 2008
1.2.3 Prefixes
Prefix Value Standard form 10n where n is Symbol Tera 1 000 000 000 000 1012 12 T 9 Giga 1 000 000 000 10 9 G Mega 1 000 000 106 6 M Kilo 1 000 103 3 k Hecto 100 102 2 h Deca 10 101 1 da Deci 0.1 10-1 -1 d -2 Centi 0.01 10 -2 c Milli 0.001 10-3 -3 m Micro 0.000 001 10-6 -6 μ Nano 0.000 000 001 10-9 -9 n -12 Pico 0.000 000 000 001 10 -12 p
1.3
Scalar and Vector Quantities
Scalar Quantities Vector Quantities Quantities with magnitude only Quantities with magnitude and direction EXAMPLES Distance Displacement Speed Velocity
Example: Distance vs Displacement
Kangar
138 km 507 km Butterworth 369 km
Fauziah travelled from Kuala Lumpur to Kangar, a distance of 507 km. After that she continued her journey to Butterworth, a distance of 138 km. From Butterworth, Fauziah then travelled back to Kuala Lumpur, a distance of 369 km. Distance is the TOTAL DISTANCE TRAVELLED...