General Science — UP Police Constable Study Notes
Overview
General Science forms a significant portion of the General Knowledge section in UP Police Constable exam, typically accounting for 8-12 questions. This section tests your understanding of fundamental scientific principles from Physics, Chemistry and Biology, with emphasis on everyday applications rather than advanced theory. Questions are straightforward and focus on concepts taught up to Class 10 level, covering topics like motion, energy, chemical reactions, human body systems, diseases and nutrition.
The exam expects factual recall combined with practical understanding — you should know not just what happens but why common phenomena occur. For instance, understanding why ice floats on water, how vaccines work, or what causes rusting. The key to scoring well is consistent revision of basic concepts, memorizing important facts (vitamins, diseases, SI units) and connecting scientific principles to daily life observations. Most questions are direct and can be answered quickly if you have solid foundational knowledge.
Focus on high-yield topics: human body systems (especially digestive, circulatory and respiratory), diseases and their causative agents, vitamins and deficiencies, basic laws of motion and energy, chemical reactions in daily life, and properties of matter. Avoid going too deep into any single area — breadth of coverage matters more than depth for this exam.
Key Concepts
• **States of Matter**: Matter exists in solid, liquid, gas and plasma states. Solids have fixed shape and volume; liquids have fixed volume but take container shape; gases have neither fixed shape nor volume. Changes between states involve heat energy (melting, freezing, evaporation, condensation, sublimation).
• **Laws of Motion**: Newton's three laws govern movement — objects remain at rest/motion unless acted upon by force; force equals mass times acceleration (F = ma); every action has equal and opposite reaction. These explain everyday phenomena like seat belts, rocket propulsion and recoil of guns.
• **Energy Conservation**: Energy cannot be created or destroyed, only converted from one form to another. Common conversions include electrical to light (bulb), chemical to mechanical (engine), solar to electrical (solar panel) and potential to kinetic (falling object).
• **Acids, Bases and Salts**: Acids taste sour, turn blue litmus red and have pH < 7 (HCl, H₂SO₄). Bases taste bitter, turn red litmus blue and have pH > 7 (NaOH, Ca(OH)₂). Neutralization produces salt and water. pH 7 is neutral (pure water).
• **Cell Structure**: Cell is the basic unit of life. Plant cells have cell wall, chloroplasts and large vacuole; animal cells lack these. Nucleus controls cell activities, mitochondria produce energy, ribosomes synthesize proteins and chloroplasts perform photosynthesis in plants.
• **Human Body Systems**: Digestive system breaks down food (mouth → stomach → small intestine → large intestine). Circulatory system transports blood (heart pumps blood through arteries and veins). Respiratory system exchanges gases (lungs absorb oxygen, expel carbon dioxide). Nervous system coordinates body functions through brain, spinal cord and nerves.