Basic Sciences and Humanities: Reasoning, Language and Quantitative Aptitude
Core concepts
This domain blends basic science reasoning with language and quantitative aptitude. Expect questions on units and measurement (SI base units, conversions), basic physics and chemistry concepts (density, pH, states of matter), and elementary biology and environment. Alongside these sit verbal ability (synonyms, antonyms, idioms, sentence correction), reading comprehension, and quantitative aptitude (percentages, ratio and proportion, averages, time-speed-distance, simple interest).
Humanities content usually covers Indian history, polity and geography at a general level: the Constitution, fundamental rights, states and capitals, and basic economic terms. Reasoning sections test series completion, analogies, coding-decoding and blood relations.
Traps
In aptitude, the trap is unit mismatch - mixing minutes with hours, or grams with kilograms. In language, watch for near-synonyms that differ in tone, and for idioms that cannot be decoded literally. In polity, distinguish fundamental rights from directive principles (rights are justiciable, principles are not). In series questions, check for two interleaved patterns before assuming a single rule.
Worked rule of thumb
Always convert to one unit first, then compute. Example: a train covers 90 km in 1 hour 30 minutes. Convert time to 1.5 hours, then speed = 90 ÷ 1.5 = 60 km/h. If asked for metres per second, multiply by 5/18: 60 × 5/18 ≈ 16.7 m/s. This single conversion habit resolves most speed and ratio errors.
For percentage change, use change ÷ original × 100, and remember that a 20% increase followed by a 20% decrease does not return to the original value (it ends 4% lower).