Everyday Science — Past Papers — Part 6 MCQs with Explanations

Very high frequency is the ITU designation for the range of radio frequency electromagnetic waves from 30 to 300 megahertz, with corresponding wavelengths of ten to one meter. ND17-7-2023

The pitch of a sound wave depends on its frequency . Pitch tells us whether a sound is high or low . Higher frequency → higher pitch (e.g., whistle). Lower frequency → lower pitch (e.g., bass drum). Frequency is measured in Hertz (Hz).

The law of universal gravitation was proposed by Isaac Newton . He introduced it in 1687 in his famous book Principia . It explains that every object attracts every other object . The force depends on mass and distance .

Mumps and measles are prevented mainly through vaccination . Both mumps and measles are viral diseases . The MMR vaccine protects against Measles, Mumps, and Rubella .

Main transmission: Contaminated water and food. Disease: Cholera . Causative organism: Vibrio cholerae. Major symptom: Severe watery diarrhea. Prevention: Safe water, sanitation, and good hygiene .

Ozone (O₃) is mainly found in the Stratosphere , called the ozone layer . It absorbs harmful ultraviolet (UV) radiation from the sun, protecting life on Earth . Located roughly 15–35 km above the Earth’s surface.

In forensic science, Chromatography is commonly used for identifying poisons, drugs, and other chemicals . It is a laboratory technique used to separate, identify, and analyze different substances in a mixture. It can help detect toxic substances in blood, urine, and other biological samples .

Ophthalmology is the study and medical specialty concerned with the eyes and vision . It deals with the structure, function, diseases , and treatment of the eyes. A doctor specializing in this field is called an ophthalmologist . Common eye conditions include cataracts, glaucoma, and refractive errors .

A pH meter is an electronic instrument used to measure the acidity or alkalinity of a liquid solution by determining hydrogen-ion activity. Glass electrode: Senses hydrogen ions in the liquid. Reference electrode: Provides a stable electrical voltage. Meter display: Converts the voltage difference into a clear pH number

Gravimetric analysis is a quantitative analytical method . It determines the amount of an analyte by measuring its mass . The measured mass is used to calculate the amount of the original substance.

Filtration separates solid particles from a liquid or gas based on particle size. A porous material (filter) allows fluid and small particles through The liquid that passes through is called the filtrate The solid left behind on the filter is called the residue It works only when the solid particles are larger than the filter's pores Examples: Coffee filter separating grounds from liquid coffe e

Based on differences in boiling points Lower-boiling-poin t liquid vaporizes first Vapor is collected and condensed back into a liquid Higher-boiling-point liquids remain behind Used to separate and purify liquid mixtures (e.g., water and ethanol)

Dinosaurs are part of the reptile group, specifically a diverse group of reptiles that appeared during the Mesozoic Era. They were the dominant terrestrial vertebrates for over 160 million years.

Geologists are scientists who study a planet's solid features, like soil, rocks, and minerals. while The study of the general physical characteristics of rocks is called Lithology petrology is a branch of geology that is concerned with the structure, composition, and distribution of rocks. petrogenesis deal with the study of the origin of rock ND31-12-2022

China has successfully landed a robot on the surface of Mars on 15 May 2021. China has become the third country after Russia and the United States of America in history The rover ' Zhurong ' will spend around 90 Martian days on the planet. A Martian day is around 24 hours and 39 minutes. This rover is named after the mythical Chinese god of fire.

Isaac Newton formulated the law of universal gravitation , explaining how gravity works. He famously described gravity after observing an apple fall from a tree .

Heterotrophs are those organisms that cannot prepare their food from nature Hence depend on other organisms that produce food (autotrophs). Non-green plants cannot make their food due to the absence of chlorophyll in their leaves

The spleen is often referred to as the "graveyard of RBCs" Because it is responsible for filtering and breaking down old, damaged, and worn-out red blood cells (RBCs).

Antoine Henri Becquerel was an engineer, physicist, Nobel laureate, First person to discover evidence of radioactivity . He belonged to France .

The time period of a charged particle in a uniform magnetic field: Formula:T=2πm/ qB Here, m = mass, q = charge, and B = magnetic field strength. Notice the velocity v does not appear in this formula — the period depends only on mass, charge, and field strength.

Carbon monoxide (CO) binds strongly with hemoglobin in the blood. It forms carboxyhemoglobin (COHb), reducing the blood's oxygen-carrying capacity. CO binds to hemoglobin about 200–250 times more strongly than oxygen. This can lead to oxygen deficiency (hypoxia) in body tissues. Carbon monoxide is a colorless, odorless, and poisonous gas.

Urine is produced in the kidneys by filtering the blood. The kidneys remove excess water, salts, and waste products from the blood. Urine is formed in tiny filtering units called nephrons . After formation, urine passes through the ureters to the urinary bladder. The kidneys help maintain the body's fluid and electrolyte balance.

William Harvey discovered the circulation of blood . He was the first physician to completely describe systemic blood circulation . Famous book: De Motu Cordis ( On the Motion of the Heart and Blood ) (1628) He is known as the Father of Circulation of Blood . Additional information : Birth: 1578 Death: 1657

Tritium (³H) is the radioactive isotope of hydrogen . It undergoes beta (β) decay and changes into Helium-3 . Additional information : Hydrogen Isotopes: 3 (Protium, Deuterium, Tritium) Protium (¹H) : 1 proton, 0 neutrons ( Stable ) Deuterium (²H) : 1 proton, 1 neutron (Stable) Tritium (³H) : 1 proton, 2 neutrons ( Radioactive ) Half-life of Tritium : Approximately 12.3 years

The Induced Fit Model was proposed by Daniel Koshland in 1958. The enzyme active site is flexible , not rigid. Substrate binding induces a shape change in the enzyme. The perfect fit is achieved after binding, not before.

Area of wall = Height × Length = 8 × 24 = 192 ft² Given: 10 gallons cover 75 ft² Required paint frac{192 times 10}{75} = 25.6 192/75 × 10 ​ = 25.6

Formula: Efficiency = 1 − (T₂/T₁) Convert to Kelvin: 27°C = 300 K 277°C = 550 K Efficiency = 1 − (300/550) = 45.45%

Formula: M = 1 + D/f D = 25 cm f = 5 cm M = 1 + 25/5 = 1 + 5 = 6

Time period = 24 hours = 86400 seconds Formula: f = 1/T f = 1/86400 ≈ 1.16 × 10⁻⁵ Hz

Formula: Phase difference = (2π/λ) × Path difference π = (2π/λ) × Path difference Path difference = λ/2

The vestibular apparatus of the inner ear maintains balance during head movement. It detects the position and movement of the head . The semicircular canals detect rotational (angular) movements. The utricle and saccule detect linear acceleration and head position. The brain combines these signals to maintain posture and balance .

In fluvial processes, small and shallow channels are called rills, which grow into gullies, Additional information Valleys: Large, low-lying areas drained by rivers or streams. Deltas: Landforms created at the mouth of a river where it meets standing water. Levees: Raised ridges of sediment running along the banks of a river channel.

The visible light spectrum for the human eye generally ranges from approximately 380 to 750 nanometers (nm), with standard limits often cited from 400 to 700 nm. Wavelength Ranges by Color Violet: 380 nm to 450 nm Blue: 450 nm to 485 nm Green: 485 nm to 500 nm Yellow: 500 nm to 565 nm Orange: 565 nm to 625 nm Red: 625 nm to 750 nm Last updated 27-07-2026 by NA

Slate is a metamorphic rock. It is mainly formed from shale or mudstone. Formation occurs under low-grade heat and pressure. Volcanic ash can also contribute to its formation. Type: Fine-grained, foliated metamorphic rock. Last updated 27-07-2026 by NA

SI stands for the International System of Units The world's standard modern metric system used for science, commerce, and everyday measurements. The SI system is built upon seven fundamental base units: Metre (m) – for length Kilogram (kg) – for mass Second (s) – for time Ampere (A) – for electric current Kelvin (K) – for thermodynamic temperature Mole (mol) – for amount of substance Candela (cd) – for luminous intensity Last updated 27-07-2026 by NA

When tectonic plates slide past each other , they form faults or fault lines . This type of plate boundary is called a transform boundary . Movement along fault lines can cause earthquakes . A famous example is the San Andreas Fault in California, USA .

A horst is an uplifted block of the Earth's crust formed between two parallel normal faults. It is created by tectonic forces during crustal extension. The adjacent blocks move downward , making the horst appear elevated. Additional information : Graben : Down-faulted block between two normal faults Normal fault : Forms due to tensional forces Reverse fault : Forms due to compressional forces Strike-slip fault : Forms due to horizontal shearing forces

Einstein's equation E=mc² shows that mass can be converted into energy and vice versa . c: Speed of light = 299,792,458 m/s (≈ 3×10⁸ m/s) E: Energy m: Mass It was proposed by Albert Einstein in 1905 as part of the Special Theory of Relativity .

Cow and Deer are herbivores because they feed on plants . Herbivores eat grass, leaves, fruits, and other plant materials. Additional information : Herbivores: Cow, Deer, Goat, Rabbit, Elephant Carnivores : Lion, Tiger, Leopard, Wolf, Cheetah Omnivores : Human, Bear, Crow, Pig, Hen

Paramecium contains two nuclei : a macronucleus and a micronucleus . The macronucleus controls daily metabolic and cellular activities. The micronucleus is responsible for reproduction and genetic exchange. Paramecium is a single-celled protozoan found in freshwater . It belongs to the phylum Ciliophora .