General Science Questions for RRB NTPC

Physics — Core Concepts

Physics questions in RRB NTPC revolve around Newton's laws, units and measurements, sound, light, electricity, and magnetism. You do not need derivations — just understand what each law says and its real-life example. For instance, Newton's Third Law explains rocket propulsion and recoil of a gun.

• SI unit of Force is Newton (N), Energy is Joule (J), Power is Watt (W), Pressure is Pascal (Pa)
• Speed of light in vacuum: 3 x 10^8 m/s. Speed of sound in air at 0°C: 332 m/s
• Decibel (dB) measures sound intensity. Normal conversation is around 60 dB
• Concave mirror is used in headlights, torches, shaving mirrors. Convex mirror used in rear-view mirrors
• Ohm's Law: V = IR. Resistance increases with temperature in metals
• Transformer works on electromagnetic induction (Faraday's law). It only works with AC, not DC

Chemistry — Key Facts

Chemistry questions focus on acids and bases, pH scale, common chemical compounds, metals and non-metals, and everyday chemical reactions. Remember: acids taste sour and turn blue litmus red; bases taste bitter and turn red litmus blue. The pH scale runs from 0 to 14, with 7 being neutral.

• pH less than 7 is acidic (lemon juice pH 2, vinegar pH 3). pH more than 7 is basic (baking soda pH 9, bleach pH 13)
• Water formula H2O, Salt is NaCl, Baking soda is NaHCO3, Washing soda is Na2CO3
• Rusting of iron requires both oxygen and water. It is an oxidation reaction
• Nitrogen is the most abundant gas in atmosphere (78%), then Oxygen (21%), Argon (0.93%)
• Gold and Platinum are noble metals — they do not react easily. Iron, Aluminium are common reactive metals
• Ozone (O3) layer is in stratosphere and absorbs harmful UV radiation from Sun

Biology — Human Body and Life Science

Biology is the highest-scoring science area in RRB NTPC. Questions target vitamins and their deficiency diseases, blood groups, human digestive and circulatory systems, cell biology basics, and common diseases with their causative agents. Memorise the vitamin table and disease-pathogen pairs — they appear almost every exam.

• Vitamin A (Night blindness), B (Beriberi, Pellagra), C (Scurvy), D (Rickets), K (Blood clotting failure)
• Blood groups: A, B, AB (universal recipient), O (universal donor). Rh factor also matters
• Red Blood Cells (RBC) carry oxygen using haemoglobin. White Blood Cells (WBC) fight infection. Platelets help in clotting
• Largest organ: Skin. Largest internal organ: Liver. Largest gland: Liver. Smallest bone: Stapes (in ear)
• Malaria caused by Plasmodium parasite via Anopheles mosquito. Dengue by Aedes mosquito (virus)
• Photosynthesis: plants use sunlight, CO2, water to make glucose and release oxygen. Chlorophyll is the green pigment responsible

Diseases — Causative Agents Quick Reference

RRB NTPC frequently asks which organism causes which disease. Diseases are caused by bacteria, viruses, fungi, or parasites. Knowing the category helps eliminate wrong options quickly. A simple rule: most respiratory and childhood diseases are viral; food poisoning and TB are bacterial.

• Viral diseases: Common cold, Influenza, Rabies, Polio, HIV/AIDS, Dengue, Chickenpox
• Bacterial diseases: Tuberculosis (TB), Cholera, Typhoid, Leprosy (Hansen's disease), Plague
• Parasitic diseases: Malaria (Plasmodium), Filariasis (Wuchereria), Amoebic dysentery
• Fungal diseases: Ringworm, Athlete's foot, Candidiasis
• Deficiency diseases: not caused by any microbe — caused by lack of nutrients (kwashiorkor = protein deficiency)

Units, Instruments and Inventions

A small but reliable source of easy marks. Questions ask what instrument measures what, or who invented what. These are pure memory items — no logic needed, just a good cheat sheet.

• Barometer measures atmospheric pressure. Thermometer measures temperature. Seismograph measures earthquakes
• Ammeter measures current (connected in series). Voltmeter measures voltage (connected in parallel)
• Penicillin discovered by Alexander Fleming. Telephone invented by Alexander Graham Bell. X-ray by Wilhelm Roentgen
• Light year is a unit of DISTANCE, not time — distance light travels in one year
• Decibel for sound intensity, Richter scale for earthquake magnitude, Knot for ship speed

• Confusing Vitamin D source: many say 'milk' but the primary source is sunlight (skin synthesis). Milk is fortified but sunlight is the natural source.
• Mixing up universal donor and universal recipient: O is donor, AB is recipient. Candidates reverse this under pressure.
• Thinking light year is a unit of time because it has the word 'year' in it — it is a unit of distance.
• Confusing concave and convex mirror uses: concave focuses light (headlights), convex diverges (rear-view). Mixing these up is a very common error.
• Assuming transformer works with DC — transformers require alternating current (AC) to work. This concept is tested as a one-liner trap.

• Vitamin trick ABCDK: A=eyeA (vision), B=Beriberi Begins, C=Cuts bleed (Scurvy), D=D for Dhadha (Bones/Rickets), K=Khooon (blood clotting). Each letter links to function.
• For blood groups: think of AB as 'All Blood welcome' (universal recipient) and O as 'Open to all' (universal donor).
• NOVA for atmosphere layers bottom to top: trOposphere, strAtosphere, mesOsphere, thermOsphere — remember 'TOST' like toast burning from the bottom.
• Rear-view mirror = Convex = C for Car safety. Headlight = Concave = C for Converging light. Both start with C but remember the purpose: safety vs spotlight.

• In RRB NTPC Phase 1, General Science questions are mostly factual one-liners. Spend no more than 30-40 seconds per question. If you do not remember, mark and move — do not guess randomly as there is negative marking.
• Biology questions appear most frequently, especially vitamins, blood, and diseases. Prepare a one-page vitamin-disease table and revise it 3 times before exam day.
• Physics questions in recent papers have focused on units and everyday applications (mirror types, transformer, sonar) rather than numerical calculations. So concept clarity matters more than formula practice here.
• Chemistry questions often include pH-based scenarios, common compounds in daily life (baking soda, bleach, vinegar), and atmospheric composition. These are repeated across multiple years.
• Watch out for tricky phrasing like 'which gas makes up most of dry air' — answer is Nitrogen (78%), not Oxygen. RRB examiners like to test if you confuse 'most abundant' with 'most needed for breathing'.