General Science
General Science tests school-level physics, chemistry and biology applied to everyday and health contexts, with numerical work kept short.
Physics
- Newton's laws: F = ma; inertia; action and reaction are equal and opposite.
- Work = force x displacement in the direction of force; power = work/time.
- Ohm's law V = IR; series resistances add; for parallel resistances 1/R = 1/R1 + 1/R2.
- Sound needs a medium and travels faster in solids; light travels far faster than sound.
Chemistry and biology
- pH below 7 is acidic, above 7 basic; acids turn blue litmus red.
- Atoms have protons and neutrons in the nucleus with electrons outside; valency drives formula writing.
- Photosynthesis: 6CO2 + 6H2O gives C6H12O6 + 6O2 in the presence of chlorophyll and light.
- Fat-soluble vitamins are A, D, E and K; vitamin A deficiency causes night blindness and vitamin D deficiency causes rickets.
Worked example
A 6 ohm and a 3 ohm resistor are connected in parallel across 12 V. Parallel resistance = (6 x 3)/(6 + 3) = 2 ohm. Current = V/R = 12/2 = 6 A. The main current splits as 2 A through 6 ohm and 4 A through 3 ohm, which adds back to 6 A as a check.
Traps
Mass is not weight; weight changes with gravity. The speed of sound is not 3 x 10^8 m/s. Always add acid to water, never water to acid.