SAJC_Physics Summary for 2025 JC1 FE_for students

SAJC H2 Physics Summary updated Oct 2025 1/38 PHYSICS H2 Physics Summary St Andrew’s Junior College H2 Name: ________________ Class: _________

SAJC H2 Physics Summary updated Oct 2025 2/38 Data speed of light in free space c = 3.00 x 108 m s-1 gravitational constant G = 6.67 x 10-11 N m2 kg-2 acceleration of free fall g = 9.81 m s-2 Formulae uniformly accelerated motion s = u t + 1 2 a t2 v2 = u2 + 2 a s pressure p = F A gravitational potential  = − Gm r displacement of particle in s.h.m. x = xo sin  t velocity of particle in s.h.m. v = v0 cos  t =   22 0 xx −

SAJC H2 Physics Summary updated Oct 2025 3/38 H2 Physics Summary (Syllabus 9478) (Definitions, Equations, Terms, Qualitative Explanations, Common Mistakes) Key: ( ) optional but good to include; { } Tutor’s comments/Common Mistakes; [ ] Alternative Term Topic 1: Quantities and Measurements 1. Base quantities (with their SI base units/ symbol): length (metre/ m), mass (kilogram/ kg), time (second/ s), amount of substance (mole/ mol), temperature (kelvin/ K), current (ampere/ A). Base units: are (a choice of well-defined) units by which all other units are expressed. Derived unit: a unit expressed as a product and/or quotient of the base units. (eg. newton, pascal, joule, watt, hertz, coulomb, volt, ohm) Unitless quantities: all numbers, trigo functions, log functions (logx, ln), powers, certain physical constants (eg. refractive index) 2. Homogeneous equations: An equation is homogeneous if every term on both sides of the equation have the same SI base units. A physically correct equation must be homogeneous. 3. Prefixes: to recall certain prefixes & their decimal equivalents: • 1012 tera (T), 10 9 giga (G), 10 6 mega (M), 103 kilo (k), 10 -1 deci (d), 10 -2 centi (c), 10 -3 milli (m), 10 -6 micro (), 10-9 nano (n), 10-12 pico (p). • Sample TYS qns: decimetre = 10-1 m; megametre = 106 m; 500 cN = 500 x 10-2 N (2016 P1Q1) 4. Making reasonable estimates of certain physical quantities: • to give the figure to 1 significant figure. {N08P1Q2, N09P1Q2} • need to express a more complicated quantity in terms of other simpler quantities using a formula first. • 'correct to an order-of-magnitude' means value quoted is reliable to within a factor of ten or so. • Significant figures: rules to follow: • All non-zero digits are significant digits • Zeros that occur between significant digits are significant digits • Zeros to the right of the decimal point and to the right of a non -zero digit are significant 5. Errors • An error is the difference between the measured value and the ‘true value’. A total error can be a combination of both systematic error and/or random error. 6. Random error: • An error {not reading} which causes measurements to be sometimes larger than the true value