Everyday Science
Instructions: How well do you understand the science behind everyday life?
- 1.
Why does ice float on water?
AIce contains air bubblesBIce is a different substance than waterCCold things always floatDIce is less dense than liquid water - 2.
What causes bread to rise when baking?
AYeast producing carbon dioxide gasBHeat from the ovenCButter melting insideDFlour absorbing water - 3.
Why does a metal spoon feel colder than a wooden spoon at the same temperature?
AMetal is actually colderBMetal conducts heat away from your hand fasterCIt's just an illusionDWood stores more warmth - 4.
What makes the sky appear blue?
AReflection from the oceanBThe ozone layer is blueCClouds filter out other colorsDBlue light is scattered more by the atmosphere - 5.
Why do onions make you cry when you cut them?
ATiny juice droplets fly into your eyesBThe strong smell irritates your eyesCIt's a psychological response to the tasteDThey release a sulfur-based gas that reacts with your tears - 6.
What causes static electricity when you rub a balloon on your hair?
AAir molecules get chargedBHeat generated by frictionCElectrons transfer between surfacesDMagnetic fields are created - 7.
Why does salt help melt ice on roads?
ASalt absorbs iceBSalt creates friction that generates heatCSalt lowers the freezing point of waterDSalt is warm - 8.
What causes thunder during a storm?
AWind blowing through rainBStatic electricity in the cloudsCRapid expansion of air heated by lightningDClouds colliding with each other - 9.
Why does a mirror reverse left and right but not up and down?
AIt actually reverses front and back, not left and rightBGravity affects the reflectionCMirrors only work horizontallyDLight bends differently vertically - 10.
Why do we see lightning before we hear thunder?
AThunder comes from farther awayBLightning happens before thunderCLight travels much faster than soundDOur eyes process faster than our ears - 11.
What keeps the Moon in orbit around the Earth?
AThe Sun's gravityBEarth's gravityCThe Moon's own momentumDEarth's magnetic field - 12.
Why does a wet shirt feel colder than a dry one?
AWater blocks body heatBWet fabric is thinnerCEvaporation draws heat away from your bodyDWater is always cold - 13.
Why do leaves change color in autumn?
ALeaves absorb different light as days shortenBTrees stop making chlorophyll, revealing other pigmentsCCold weather paints themDFrost damages the green color - 14.
What is the main gas that makes up the air we breathe?
ACarbon dioxideBOxygenCHydrogenDNitrogen - 15.
Why does hot water sometimes freeze faster than cold water?
AThis never actually happensBIt's called the Mpemba effect and isn't fully understoodCHot water has less dissolved gasDThe container warms the freezer - 16.
What makes soap effective at cleaning?
AIt kills all bacteriaBIt's acidic and dissolves dirtCIt creates a protective barrierDIts molecules attract both water and oil - 17.
Why do stars appear to twinkle?
AOur eyes can't focus on them properlyBStars are very far awayCStars actually pulse with lightDEarth's atmosphere bends their light - 18.
Why does a spinning top stay upright?
AAir pressure holds it upBThe point creates perfect balanceCCentrifugal force pushes it upDGyroscopic effect from angular momentum - 19.
What causes the 'new car smell'?
AClean metal and plasticBA special fragrance sprayed at the factoryCFresh rubber from the tiresDChemicals releasing from new materials (off-gassing) - 20.
Why does a compass needle point north?
AMagnetism from the SunBGravity pulls it northwardCIt aligns with Earth's magnetic fieldDThe North Pole has more iron
Answer Key
Water expands when it freezes, making ice less dense than liquid water. This is why ice floats — a unique property that insulates lakes in winter.
Yeast ferments sugars in the dough, producing carbon dioxide gas. These gas bubbles get trapped in the gluten network, causing the bread to rise.
Metal is a much better heat conductor than wood. It pulls heat away from your warm hand more quickly, making it feel colder even though both are the same temperature.
Sunlight is scattered by molecules in the atmosphere, and shorter blue wavelengths are scattered more than other colors — this is called Rayleigh scattering.
Cutting onions releases syn-propanethial-S-oxide, a sulfur compound that reacts with the moisture in your eyes to form a mild sulfuric acid, triggering tears.
Rubbing transfers electrons from your hair to the balloon, giving the balloon a negative charge and your hair a positive charge, causing them to attract.
Salt lowers the freezing point of water (a process called freezing point depression), causing ice to melt at temperatures below 32°F (0°C).
Lightning heats the surrounding air to about 30,000 Kelvin. This rapid heating causes the air to expand explosively, creating the sound waves we hear as thunder.
A mirror actually reverses front and back (depth), not left and right. We perceive it as a left-right reversal because we imagine turning around to face ourselves.
Light travels at about 186,000 miles per second, while sound travels at only about 1,100 feet per second. So we see the flash almost instantly but the sound takes longer to reach us.
Earth's gravitational pull keeps the Moon in orbit. The Moon is constantly 'falling' toward Earth, but its forward motion keeps it in a stable orbit.
When water evaporates from the wet shirt, it absorbs heat energy from your skin. This evaporative cooling makes you feel colder.
As days shorten, trees stop producing green chlorophyll. This reveals yellow and orange pigments (carotenoids) that were always present but masked by the green.
Nitrogen makes up about 78% of Earth's atmosphere. Oxygen is second at about 21%. Despite being essential, oxygen is not the most abundant gas.
The Mpemba effect is a real phenomenon where hot water can freeze faster than cold water under certain conditions. Scientists still debate the exact cause.
Soap molecules have one end that attracts water and another that attracts oil and grease. This allows soap to lift oily dirt from surfaces and wash it away with water.
Starlight passes through layers of Earth's atmosphere with different temperatures and densities, causing the light to bend and shift — creating the twinkling effect.
A spinning top stays upright due to the gyroscopic effect. Its angular momentum resists changes to its orientation, keeping the axis stable.
The 'new car smell' comes from volatile organic compounds (VOCs) off-gassing from new plastics, adhesives, leather, and other interior materials.
A compass needle is a small magnet that aligns with Earth's magnetic field, which is generated by convection currents in the planet's molten iron outer core.