Question 1

How do zippers work?

Accepted Answer

Zippers have two rows of metal or plastic teeth that lock together when you pull the slider. The slider moves up and down to join or separate the teeth, making it easy to open or close bags and clothes.

Question 2

Why do pencils have erasers?

Accepted Answer

Pencils come with erasers to help fix mistakes when writing or drawing. The eraser rubs off pencil marks without tearing the paper, so you can correct errors.

Question 3

How do light bulbs turn on?

Accepted Answer

When you switch on a light bulb, electricity travels through a tiny wire inside called a filament. The wire heats up and glows, which makes the bulb light up.

Question 4

What makes soap clean things?

Accepted Answer

Soap has special molecules that stick to dirt and grease and help water wash them away. This is why soap is great for cleaning our hands and dishes.

Question 5

How do clocks keep time?

Accepted Answer

Clocks use tiny moving parts or electronic pulses to keep track of time. They measure seconds, minutes, and hours so we know what time it is.

Question 6

How do magnets stick to metal?

Accepted Answer

Magnets have a force that attracts certain metals like iron. This force pulls the metal towards the magnet, making them stick together.

Question 7

Why do we have wheels on cars?

Accepted Answer

Wheels help cars move smoothly over the ground. They roll to reduce friction, making it easier for the car to go fast and change direction.

Question 8

How do cameras take pictures?

Accepted Answer

Cameras capture light through a lens and record it onto film or a digital sensor. This light forms the image you see as a photo.

Question 9

Why do phones have batteries?

Accepted Answer

Batteries store energy that powers the phone when it's not plugged in. They let you use the phone anywhere, even without an electrical outlet.

Question 10

How does a refrigerator keep food cold?

Accepted Answer

Refrigerators use a special liquid called refrigerant to absorb heat inside and release it outside. This keeps the inside cool to preserve food.

Question 11

How do airplanes fly?

Accepted Answer

Airplanes have wings that shape the air flowing around them to create lift. Engines push the plane forward, and the wings lift it into the sky.

Question 12

How does a bicycle stay balanced?

Accepted Answer

When you pedal a bicycle, the wheels spin, helping you stay upright. Your balance and the speed of the bike work together to keep it stable.

Question 13

Why do flashlights need batteries?

Accepted Answer

Flashlights use batteries to power a tiny bulb or LED inside. The batteries provide the energy needed to produce light and shine in the dark.

Question 14

How do fans make air feel cooler?

Accepted Answer

Fans spin blades to move air around, which helps sweat on your skin evaporate faster. This makes you feel cooler by reducing body heat.

Question 15

How do elevators work?

Accepted Answer

Elevators use cables and pulleys to move up and down a shaft. A motor controls the movement, taking people quickly to different floors.

Question 16

How does a stapler join papers?

Accepted Answer

When you press a stapler, it pushes a staple through the papers. Then, the ends of the staple bend to hold the pages together securely.

Question 17

Why do balloons float?

Accepted Answer

Balloons float because they are filled with a gas called helium, which is lighter than air. This makes the balloon rise until the helium escapes.

Question 18

How do washing machines clean clothes?

Accepted Answer

Washing machines spin clothes in water with soap to get rid of dirt. The spinning action and soapy water work together to clean everything off.

Question 19

How does a toaster work?

Accepted Answer

A toaster uses electricity to heat up wires inside. These hot wires toast bread until it’s crispy and brown, just the way you like it.

Question 20

How do umbrellas keep us dry?

Accepted Answer

Umbrellas have a waterproof fabric stretched over a frame. When it rains, the fabric blocks the raindrops, keeping us dry underneath.

The Mechanics of Everyday Inventions - 20 FAQs Explained Simply