General Science: School-Level Physics, Chemistry, Biology
General Science here is school-level physics, chemistry and biology, with a tilt towards topics that connect to forests, health and everyday observation.
Physics
- Units and measurement: SI base units; 1 km/h = 5/18 m/s.
- Motion: distance vs displacement, speed vs velocity, acceleration; the three equations of motion.
- Force, work, energy and power; laws of reflection and refraction; sound needs a medium and travels fastest in solids.
- Electricity: Ohm's law, series vs parallel resistance, heating effect of current.
Chemistry
- Atomic number vs mass number; isotopes; symbols of the first 20 elements.
- Acids, bases, salts and pH; common formulae - quicklime CaO, slaked lime Ca(OH)₂, baking soda NaHCO₃, washing soda Na₂CO₃, gypsum CaSO₄·2H₂O.
- Metals and non-metals; alloys: brass = Cu + Zn, bronze = Cu + Sn.
Biology
- Cell organelles and functions; plant cell has a cell wall and chloroplasts, animal cell does not.
- Photosynthesis, respiration, transpiration.
- Human systems: digestive, circulatory, respiratory, excretory; blood groups.
- Vitamins and deficiency diseases: A–night blindness, B1–beriberi, C–scurvy, D–rickets.
- Vectors: malaria–female Anopheles, dengue–Aedes, kala-azar–sandfly.
Worked example
A jeep travels at 72 km/h for 15 seconds. How far does it go? Convert first: 72 × 5/18 = 20 m/s. Distance = 20 × 15 = 300 m. Converting before multiplying is what makes the options fall away.
Traps
- Mass (kg) vs weight (newton).
- Average speed is not the average of the speeds.
- Deficiency diseases paired with the wrong vitamin.
- Sound travels fastest in solids, not in air.