General Science
This domain tests school-level physics, chemistry, biology, health and environment. HP Patwari questions are usually factual and application-based: units, laws, human body systems, nutrition, diseases and common scientific phenomena.
Core rules
- SI units: metre, kilogram, second, ampere, kelvin, mole and candela. Speed = distance / time; force = mass × acceleration.
- Sound needs a material medium; it cannot travel through a vacuum. Light travels in straight lines and can be reflected or refracted.
- pH below 7 is acidic, 7 is neutral and above 7 is basic. Acids turn blue litmus red; bases turn red litmus blue.
- Plant cells have a cell wall and chloroplasts; animal cells do not. Photosynthesis uses carbon dioxide, water and sunlight to make glucose and oxygen.
- Vitamins and deficiency diseases: vitamin A and night blindness, vitamin C and scurvy, vitamin D and rickets, iron and anaemia.
Worked example
A car covers 150 km in 3 hours. Its speed is 150/3 = 50 km/h. In the next 2 hours at the same speed it covers 50 × 2 = 100 km. Reason: keep the rate constant and multiply by the additional time.
Traps that cost marks
Mass and weight are not the same; weight changes with gravity. Sound does not travel in vacuum. A plant cell has a cell wall, but an animal cell does not. Do not reverse the litmus tests.