Everyday Science — Past Papers — Part 7 MCQs with Explanations

Lahore's smog is mainly caused by pollutants from vehicles reacting with sunlight . Nitrogen oxides (NOₓ) and volatile organic compounds (VOCs) form ground-level ozone and fine particles. Industrial emissions, crop residue burning , and brick kilns also worsen smog. Smog is most severe during the winter season (October–January).

Imam Ja'far al-Sadiq (RA) was an expert in chemistry . Birth: 702 AD ( 83 AH) Death: 765 AD ( 148 AH) Imam Number: 6th Imam Student: Jabir ibn Hayyan (Geber) Known Fields: Chemistry, Fiqh, Hadith, Astronomy, Mathematics

Plastic is generally an amorphous (non-crystalline) material and does not naturally form crystals. Diamond is a crystalline form of carbon with a regular atomic structure. Sucrose (sugar) naturally forms crystals . Crystalline materials have atoms arranged in a regular repeating pattern. Amorphous materials lack a long-range ordered crystal structure.

A Panacea means a universal remedy or a medicine believed to cure all diseases. The term comes from Greek mythology , where Panacea was the goddess of universal healing . In modern medicine, no real panacea exists for all diseases. A vaccine prevents specific diseases. An antibiotic treats bacterial infections. The term panacea is often used figuratively to describe a solution claimed to solve every problem.

Ginger is an underground modified stem called a rhizome. It stores nutrients . It helps in vegetative propagation.

Alluvium is the soil, sand, silt, clay, and gravel deposited by flowing rivers and streams. It forms fertile plains that are highly suitable for agriculture. The Indus Plain of Pakistan is largely made up of alluvial deposits. Additional information : Alluvial fans are fan-shaped deposits formed where a river leaves a mountainous area. Albedo is the measure of how much sunlight a surface reflects and is unrelated to river deposits.

Mushrooms are heterotrophs and cannot make their own food . They obtain nutrients by absorbing them from dead and decaying organic matter or from living organisms. Fungi lack chlorophyll , so they cannot perform photosynthesis . Fungi belong to the Kingdom Fungi .

Geostationary satellites are located directly above the equator. Altitude: About 35,786 kilometers (22,236 miles) above sea level. Speed and Direction: Moves from west to east, matching the Earth's rotation speed. Time Period: Exactly 24 hours (one rotation day). Last updated 26-07-2026 by NA

A vegan avoids animal products, including meat, dairy, eggs, and often other animal-derived product s. Additional information Vegetarian: Does not eat meat, but may eat dairy and eggs. Carnivore: Eats only meat. Omnivore: Eats both plants and meat. Last updated 26-07-2026 by NA

A Pycnocline is an ocean layer where water density changes rapidly with depth . Density changes mainly due to variations in temperature and salinity. It acts as a barrier that limits the mixing of surface and deep waters. Additional information : Thermocline : Rapid change in temperature Halocline : Rapid change in salinity

Sunlight travels at the speed of light (~3 × 10⁸ m/s). Takes 8 minutes 20 seconds on average to reach Earth. Sunlight takes approximately 499 seconds to travel from the Sun to Earth . Distance traveled: 150 million km from Sun to Earth. Moonlight takes only 1.3 seconds to reach Earth.

A rainbow is produced due to the dispersion of sunlight by water droplets in the atmosphere. White sunlight splits into seven colours when it passes through raindrops. The formation of a rainbow involves refraction, dispersion, and internal reflection . Dispersion is the phenomenon responsible for separating white light into its constituent colours . Rainbows are usually seen opposite the Sun after rainfall .

Mathematics is widely known as the " Mother of All Sciences ". Because it provides the foundation for scientific and technological disciplines . It is essential for physics, chemistry, engineering, economics , and computer science . Mathematical principles are used in measurement, calculations, modeling, and problem-solving . The word Mathematics comes from the Greek word " Mathema ," meaning knowledge or learning .

Blood pressure readings use two numbers: systolic (top) and diastolic (bottom). An ideal normal reading is less than 120/80 mm Hg. Cardiac output: More blood pumped by the heart → higher BP . Blood volume: Increased blood volume → increased BP. Last updated 25-07-2026 by NA

EAX is a 32-bit register, meaning it can hold 4 bytes of data Its sub-parts: AX — the lower 2 bytes (16-bit) AH — the upper 1 byte (high byte of AX) AL — the lower 1 byte (low byte of AX) Last updated 24-07-2026 by NA

A commercial Polaroid — referring to the polarizing material/filter used in various commercial applications — can be called by any of these names: Polarizer — a general term for anything that polarizes light Polaroid filter — specifically referencing the Polaroid brand of polarizing filters Polarizing filter — a technical term describing the function (a filter that polarizes light) Last updated 24-07-2026 by NA

For the point (6,9) ( 6 , 9 ) : x 2 + y 2 = 6 2 + 9 2 = 36 + 81 = 117 Since 117 > 100 , the point (6,9) lies outside the circle . Last updated 24-07-2026 by NA

The Law of Cosines is used to find a side or angle of a non-right triangle. It relates three sides and one angle of a triangle. a,b,c represent the sides of the triangle. C is the angle opposite side c. It generalizes the Pythagorean theorem for any triangle . Last updated 24-07-2026 by NA

Germs are microorganisms that can cause disease. When germs enter a wound, they may cause an infection. Keeping germs out of wounds helps prevent infection. Last updated 24-07-2026 by NA

The critical temperature of mercury is approximately 4.2 K . Effect: Electrical resistance drops to zero below this point. Celsius: ~-269 °C Atomic number (Z) : 80 Group: group 12 Period: period 6 Block: d-block Electron configuration: [Xe] 4f14 5d10 6s2 Electrons per shell: 2, 8, 18, 32, 18, 2 Last updated 24-07-2026 by NA

Rutherford’s gold foil experiment (1911) showed that an atom has a small, dense, positively charged center called the nucleus . The mass of the atom is concentrated in the nucleus , while most of the atom is empty space . Additional information : Nucleus contains : Protons (+) and neutrons (neutral) Electrons move around the nucleus in mostly empty space The experiment involved alpha particles being deflected by the nucleus.

Kelvin = °C + 273 27 + 273 = 300 K .

Electromagnetic induction was discovered by Michael Faraday in 1831 . It is the production of an electric current by a changing magnetic field. This discovery led to the development of electric generators and transformers .

A Leap Year is an astronomical year with an extra day . Additional information : Leap Year: 366 days ( February has 29 days). Common Year: 365 days (February has 28 days). Solar Year: Approximately 365.2422 days (Earth's revolution around the Sun). Lunar Year: About 354 days (12 lunar months). Recent Leap Years: 2016, 2020, 2024, 2028, 2032.