Science Quiz Questions and Answers

50 science questions with answers: physics, chemistry, the body, Earth and technology.

50 questions · tap “Show answer” under each one · Answer key

Play online

Science Quiz for Kids 1Science & Nature · Worldwide · 10 questions

What is the SI unit of energy?
Show answer
Joule
It's named after James Prescott Joule. Source
What does a voltmeter measure?
Show answer
Voltage
An ammeter measures current. Source
Which color of visible light has the longest wavelength?
Show answer
Red
Violet has the shortest. Source
Which force slows things that slide over a surface?
Show answer
Friction
Without friction, you couldn't walk. Source
In E = mc², what does E stand for?
Show answer
Energy
m is mass and c is the speed of light. Source
What is it called when light bounces off a mirror?
Show answer
Reflection
The angle in equals the angle out. Source
What kind of wave is sound in air?
Show answer
Longitudinal
The air vibrates back and forth along the wave's direction. Source
What is the bending of waves around the edge of an obstacle called?
Show answer
Diffraction
It's why you can hear someone around a corner. Source
What kind of energy is stored in a stretched rubber band?
Show answer
Elastic potential energy
It turns into kinetic energy when you let go. Source
What does LED stand for?
Show answer
Light-emitting diode
LEDs use far less power than old bulbs. Source
Which element has the symbol He?
Show answer
Helium
Helium is the second lightest element. Source
What is H₂SO₄ commonly called?
Show answer
Sulfuric acid
It's used in car batteries. Source

What is dry ice made of?
Show answer
Frozen carbon dioxide
It turns straight into gas at about −78 °C. Source
What is the atomic number of carbon?
Show answer
6
Every carbon atom has six protons. Source
What is a substance that speeds up a reaction without being used up?
Show answer
A catalyst
Enzymes are catalysts in living things. Source
Roughly what is the pH of lemon juice?
Show answer
2
Lower pH means more acidic. Source
What is an atom with an electric charge called?
Show answer
An ion
Salt is made of sodium and chloride ions. Source
What is the chemical formula of methane?
Show answer
CH₄
NH₃ is ammonia. Source
Which element was found in the Sun before it was found on Earth?
Show answer
Helium
Its name comes from Helios, Greek for 'Sun'. Source
Which is the most common state of ordinary matter in the universe?
Show answer
Plasma
Stars are made of plasma. Source
Which blood type can receive red blood cells from all other types?
Show answer
AB positive
It's called the universal recipient. Source
How many pairs of ribs do most people have?
Show answer
12
A few people have an extra rib. Source
What is the medical name for the windpipe?
Show answer
Trachea
It carries air to the lungs. Source
Which part of the brain helps control balance?
Show answer
Cerebellum
Cerebellum means 'little brain' in Latin. Source
Which pigment gives skin and hair their color?
Show answer
Melanin
More melanin means darker skin and better protection from UV light. Source

Play online

Which condition is linked to problems with insulin?
Show answer
Diabetes
Insulin helps cells take in sugar from the blood. Source
Which mineral do red blood cells need to carry oxygen?
Show answer
Iron
Too little iron causes anemia. Source
What is the clear front part of the eye called?
Show answer
Cornea
The cornea helps focus light. Source
Which part of a cell controls what goes in and out?
Show answer
Cell membrane
It's a thin double layer of fats. Source
What is a scientist who studies insects called?
Show answer
Entomologist
Ornithologists study birds. Source
What is Earth's outermost layer called?
Show answer
The crust
The crust is thinnest under the oceans. Source
Which kind of rock forms when lava cools?
Show answer
Igneous
Basalt and granite are igneous rocks. Source
What is a scientist who studies rocks called?
Show answer
Geologist
Geology is the study of Earth. Source
What is the layer of gases around Earth called?
Show answer
The atmosphere
Most of it lies within 16 km of the ground. Source
Which layer protects Earth from much of the Sun's UV rays?
Show answer
The ozone layer
It lies in the stratosphere. Source
What is a scientist who studies the weather called?
Show answer
Meteorologist
The word comes from the Greek for 'things high up'. Source
What was the supercontinent that broke apart about 200 million years ago?
Show answer
Pangaea
Gondwana and Laurasia were its two halves. Source

Which is the softest mineral on the Mohs scale?
Show answer
Talc
Talc is used to make baby powder. Source
Which layer of Earth is liquid?
Show answer
The outer core
Moving liquid iron there creates Earth's magnetic field. Source
Which is the largest desert in the world, counting cold deserts?
Show answer
Antarctica
A desert is a place with very little rain or snow. Source
Who developed the first widely used polio vaccine, in 1955?
Show answer
Jonas Salk
He chose not to patent it. Source
What does 'AI' stand for?
Show answer
Artificial intelligence
The term was coined in 1955. Source
What does 'USB' stand for?
Show answer
Universal Serial Bus
USB first appeared in 1996. Source
Which was the first car to be mass-produced on a moving assembly line?
Show answer
Ford Model T
More than 15 million were made. Source
What does a solar panel turn sunlight into?
Show answer
Electricity
Solar cells are mostly made of silicon. Source
Which writer created the 'Three Laws of Robotics'?
Show answer
Isaac Asimov
They first appeared in a 1942 story. Source
What is the smallest unit of digital information?
Show answer
A bit
A bit is a 0 or a 1. Source
How many bits are in a byte?
Show answer
8
One byte can store one letter of text. Source
Which device turns sound into electrical signals?
Show answer
A microphone
A speaker does the opposite. Source
What is 3D printing also called?
Show answer
Additive manufacturing
Objects are built up layer by layer. Source

Answer key

Joule
Voltage
Red
Friction
Energy
Reflection
Longitudinal
Diffraction
Elastic potential energy
Light-emitting diode
Helium
Sulfuric acid
Frozen carbon dioxide
6
A catalyst
2
An ion
CH₄
Helium
Plasma
AB positive
12
Trachea
Cerebellum
Melanin
Diabetes
Iron
Cornea
Cell membrane
Entomologist
The crust
Igneous
Geologist
The atmosphere
The ozone layer
Meteorologist
Pangaea
Talc
The outer core
Antarctica
Jonas Salk
Artificial intelligence
Universal Serial Bus
Ford Model T
Electricity
Isaac Asimov
A bit
8
A microphone
Additive manufacturing