Science – Medium Level – GK Questions

BCG (Bacillus Calmette-Guérin) vaccine provides immunity against tuberculosis, especially severe forms in children. Part of India's Universal Immunization Programme. [[MoHFW Guidelines, NCERT Biology Class 12]]

Alkanes are saturated hydrocarbons with single bonds: CₙH₂ₙ₊₂ (e.g., methane CH₄, ethane C₂H₆). Alkenes: CₙH₂ₙ; Alkynes: CₙH₂ₙ₋₂. Foundational organic chemistry. [[NCERT Chemistry Class 11]]

5G uses three spectrum bands: low-band (<1 GHz), mid-band (1-6 GHz), and high-band mmWave (24-47 GHz). Each offers different coverage/speed trade-offs. Important for tech awareness. [[TRAI Reports, NITI Aayog]]

Newton's law: F ∝ 1/r². Doubling distance (r→2r) reduces force to F/4. Inverse-square law applies to gravity, light intensity, etc. [[NCERT Physics Class 11]]

Oxidation is loss of electrons (OIL: Oxidation Is Loss); reduction is gain of electrons (RIG). Mnemonic helps avoid confusion in redox reactions. [[NCERT Chemistry Class 11]]

EM spectrum order (longest to shortest wavelength): Radio > Microwave > IR > Visible > UV > X-ray > Gamma. Radio waves used in communication; gamma rays in cancer treatment. [[NCERT Physics Class 12]]

Most mammals are viviparous (live birth), but monotremes like platypus and echidna are oviparous (egg-laying). Exceptions are important for taxonomy questions. [[NCERT Biology Class 11]]

Displacement (shortest path) is always ≤ distance traveled (actual path). They are equal only for straight-line motion without direction change. Fundamental kinematics concept. [[NCERT Physics Class 11]]

Condoms (male/female) physically block sperm-egg contact, also preventing STIs. Barrier methods differ from hormonal (pills) or surgical (sterilization) methods. Important for health awareness. [[NCERT Biology Class 12, MoHFW Guidelines]]

Adsorption releases heat (ΔH < 0) as gas molecules lose freedom on surface. Desorption is endothermic. Important for catalysis and purification processes. [[NCERT Chemistry Class 12]]

IoT refers to interconnected devices (sensors, appliances) exchanging data via internet. Applications include smart homes, healthcare, agriculture. Emerging topic for tech awareness. [[NITI Aayog Reports]]

Meiosis produces four genetically unique haploid cells (gametes) due to crossing over and independent assortment. Mitosis produces two identical diploid cells. Critical for genetics. [[NCERT Biology Class 11]]

Shelter belts (windbreaks) are rows of trees/shrubs that reduce wind erosion, conserve moisture, and protect crops. Part of sustainable agriculture practices. [[NCERT Geography Class 11, MoA Reports]]

Pitch depends on frequency (higher frequency = higher pitch). Amplitude determines loudness. Confusing these is a common exam trap. [[NCERT Physics Class 9]]

Diamond is an allotrope of carbon with tetrahedral sp³ hybridization, forming a rigid 3D network. This structure gives extreme hardness. Graphite is another carbon allotrope with different properties. [[NCERT Chemistry Class 11]]

When light moves from denser (e.g., glass) to rarer medium (e.g., air) at angle > critical angle, it reflects entirely back. Used in optical fibers, prisms. Fundamental optics principle. [[NCERT Physics Class 12]]

Pancreatic beta cells (in Islets of Langerhans) secrete insulin, which lowers blood glucose by facilitating cellular uptake. Deficiency causes diabetes mellitus. Key physiology concept. [[NCERT Biology Class 11]]

The UN's 2030 Agenda has 17 SDGs with 169 targets addressing poverty, inequality, climate change, etc. India actively participates in SDG implementation. Crucial for current affairs. [[NITI Aayog SDG Reports, NCERT Geography Class 11]]

Candela (cd) is one of seven SI base units, measuring luminous intensity in a given direction. Lumen measures total luminous flux; lux measures illuminance. Important for photometry. [[NCERT Physics Class 11]]

Bernoulli's principle: in a flowing fluid, pressure decreases as speed increases (conservation of energy). Explains airplane lift, venturi effect. Common misconception in exams. [[NCERT Physics Class 11]]