Physics · Unit 1

What is Physics?

The science of how the world works

Physics is the attempt to describe the behaviour of everything with the smallest possible number of rules, and its ambition is the reason it looks so abstract from outside.

The unit is an orientation: the branches of the subject and what each one asks, matter and energy as the two things it keeps track of, the physicists whose names attach to the laws, and what working as one actually involves.

This unit breaks down into 20 short steps and 118 questions, starting at difficulty 1 and building to 2. Below you can see exactly what it covers, how the path is structured, and worked examples with explanations.

Steps
20
Questions
118
Difficulty
1-2

What this unit covers

  • Physics Around Us
  • Famous Physicists
  • Branches of Physics
  • Being a Scientist
  • Matter and Energy

Where this fits

The first unit in Physics. No prerequisites.

Where people slip

The famous names are shorthand for work done by many people over decades. Newton's laws and Einstein's relativity had a great deal of company, and treating physics as a relay of geniuses gets the history wrong.

How the unit is structured

What is Physics? runs as 20 short steps that unlock in order. 15 are practice rounds and 5 are challenge rounds that pull together everything before them. Questions start at difficulty 1 and climb to 2 as you progress.

Step 1 · easierStep 20 · harder

Challenge rounds

Example questions

30 real questions from this unit, with the answer and the reason behind it, grouped by what they practise. There are 118 in the unit altogether.

Being a Scientist

  • Fact or fibLevel 1

    1. A scientist should test an idea before believing it is true.

    Answer: True

    Testing ideas with careful experiments is how science checks what is true.

  • Build the sentenceLevel 2

    2. Build a sentence explaining why scientists repeat their experiments.

    Answer: Repeating an experiment makes the results more reliable

    Repeating an experiment and getting the same result shows the findings are reliable and not a fluke.

  • Choose all that applyLevel 2

    3. Which of these make an experiment more reliable and fair? Select all that apply.

    • Changing only one variable at a timecorrect
    • Keeping the control variables constantcorrect
    • Repeating the test and averaging the resultscorrect
    • Changing several variables at once to save time

    Changing one variable at a time, keeping controls constant, and repeating for an average all improve reliability; changing many variables at once ruins a fair test.

  • Fill the blankLevel 2

    4. A testable prediction that a scientist sets out to check with an experiment is called a ____.

    • hypothesiscorrect
    • conclusion
    • unit
    • measurement

    A hypothesis is a testable idea, and an experiment is designed to support or disprove it.

  • Match the pairsLevel 2

    5. Match each part of an experiment to its meaning.

    Answer: Hypothesis = A testable prediction; Independent variable = The factor you change; Dependent variable = The factor you measure; Control variable = A factor kept constant

    A hypothesis is a testable prediction, the independent variable is changed, the dependent variable is measured, and control variables are kept constant.

  • Multiple choiceLevel 2

    6. In a fair test, why do scientists change only one variable at a time?

    • So they know that variable caused any changecorrect
    • To make the experiment finish faster
    • Because equipment can only measure one thing
    • So the results are always positive

    Changing just one variable lets scientists be sure that any change in the result was caused by that one thing.

Branches of Physics

  • Choose all that applyLevel 1

    7. Which of these does physics study? Pick all that apply.

    • Lightcorrect
    • Heatcorrect
    • Electricitycorrect
    • Poetry

    Light, heat, and electricity are all studied in physics; poetry is not.

  • Fill the blankLevel 1

    8. The branch of physics that studies sound is called ____.

    • acousticscorrect
    • optics
    • biology
    • geology

    Acoustics is the branch of physics that studies sound.

  • Match the pairsLevel 1

    9. Match each branch of physics to what it studies.

    Answer: Optics = Light; Mechanics = Motion; Thermodynamics = Heat; Electromagnetism = Electricity

    Each branch of physics looks at a different part of nature.

  • Multiple choiceLevel 1

    10. Which branch of physics is all about light?

    • Opticscorrect
    • Biology
    • Cooking
    • History

    Optics is the branch of physics that studies light.

  • Fact or fibLevel 2

    11. Astrophysics is the branch of physics that applies physics to stars, galaxies, and the whole universe.

    Answer: True

    Astrophysics uses the laws of physics to explain stars, galaxies, black holes, and the universe itself.

  • Odd one outLevel 2

    12. Which of these is NOT a branch of physics?

    • Botanycorrect
    • Acoustics
    • Optics
    • Thermodynamics

    Acoustics, optics, and thermodynamics are branches of physics, but botany is the biological study of plants.

Famous Physicists

  • Choose all that applyLevel 1

    13. Which of these people were famous physicists? Pick all that apply.

    • Isaac Newtoncorrect
    • Albert Einsteincorrect
    • Marie Curiecorrect
    • William Shakespeare

    Newton, Einstein, and Curie were physicists; Shakespeare was a playwright.

  • Fact or fibLevel 2

    14. Isaac Newton and Albert Einstein were alive at the same time and worked together on gravity.

    Answer: False

    False. Newton died in 1727 and Einstein was born in 1879, so they lived over 150 years apart and never met.

  • Fill the blankLevel 2

    15. The scientist ____ used an early telescope to discover four moons orbiting Jupiter.

    • Galileocorrect
    • Newton
    • Curie
    • Faraday

    Galileo discovered Jupiter's four largest moons in 1610, strong evidence that not everything orbits the Earth.

  • Match the pairsLevel 2

    16. Match each famous physicist to what they are best known for discovering.

    Answer: Isaac Newton = Laws of motion; Albert Einstein = Theory of relativity; Marie Curie = Radioactivity; Michael Faraday = Electromagnetic induction

    Newton, Einstein, Curie, and Faraday each made a landmark discovery that shaped modern physics.

  • Multiple choiceLevel 2

    17. Which scientist won Nobel Prizes in two different sciences, Physics and Chemistry, for work on radioactivity?

    • Marie Curiecorrect
    • Albert Einstein
    • Isaac Newton
    • Galileo Galilei

    Marie Curie won the Nobel Prize in Physics in 1903 and in Chemistry in 1911 for her research on radioactivity.

  • Odd one outLevel 2

    18. Which of these people is best known as a biologist rather than a physicist?

    • Charles Darwincorrect
    • Isaac Newton
    • Michael Faraday
    • Niels Bohr

    Newton, Faraday, and Bohr were physicists, while Charles Darwin was a biologist famous for the theory of evolution.

Matter and Energy

  • Match the pairsLevel 1

    19. Match each form of energy to an everyday example.

    Answer: Light = The Sun; Heat = A campfire; Sound = A drum; Electricity = A battery

    Light, heat, sound, and electricity all show up in everyday examples.

  • Multiple choiceLevel 1

    20. What is matter?

    • Anything that has mass and takes up spacecorrect
    • A kind of light
    • A type of sound
    • A feeling in your head

    Matter is anything that has mass and takes up space.

  • Choose all that applyLevel 2

    21. Which of these are forms of energy? (Select all that apply.)

    • Kinetic energycorrect
    • Thermal (heat) energycorrect
    • Light energycorrect
    • Oxygen gas

    Kinetic, thermal, and light are all forms of energy, but oxygen is a type of matter, not energy.

  • Fact or fibLevel 2

    22. All the ordinary matter around us is built from tiny particles called atoms.

    Answer: True

    Everything you can touch is made of atoms, which themselves contain protons, neutrons, and electrons.

  • Fill the blankLevel 2

    23. The three main particles that make up an atom are protons, neutrons, and ____.

    • electronscorrect
    • photons
    • molecules
    • magnets

    Atoms are built from protons and neutrons in the nucleus with electrons moving around the outside.

  • Guess the numberLevel 2

    24. About how many degrees Celsius is absolute zero, the coldest temperature possible?

    Answer: -273 degrees C

    Absolute zero is about -273 degrees C, the point where particles have their minimum possible energy.

Physics Around Us

  • Build the sentenceLevel 1

    25. Build a sentence about what physics is the study of.

    Answer: Physics studies matter and energy

    Physics is the study of matter and energy.

  • Multiple choiceLevel 1

    26. What does physics try to explain?

    • How the world and universe workcorrect
    • How living things grow and reproduce
    • The meaning of old poems
    • How to paint pictures

    Physics studies matter, energy, forces, and motion - how the whole world and universe work.

  • Fill the blankLevel 2

    27. Ultrasound scanners build a picture of a baby by sending in ____ waves and listening for their echoes.

    • soundcorrect
    • light
    • radio
    • magnetic

    Ultrasound uses very high-pitched sound waves, and the reflected echoes are turned into an image.

  • Guess the numberLevel 2

    28. In most of Europe, mains electricity alternates back and forth at what frequency?

    Answer: 50 Hz

    European mains electricity is alternating current at 50 Hz, meaning it changes direction 50 times each second.

  • Match the pairsLevel 2

    29. Match each everyday object to the piece of physics that makes it work.

    Answer: Thermos flask = Slows heat transfer; Camera = Focuses light with a lens; Bicycle brake = Uses friction to stop; Compass = Points using magnetism

    Each object relies on a different physics idea: insulation, lenses, friction, and magnetism.

  • Odd one outLevel 2

    30. Which of these everyday things does NOT rely on magnetism to work?

    • A burning candlecorrect
    • An electric motor
    • A loudspeaker
    • A fridge magnet

    Electric motors, loudspeakers, and fridge magnets all use magnetism, but a candle simply burns fuel to give light and heat.

Where these questions come from. Each unit starts as a plan of the concepts it should cover and the difficulty it should span. Questions are written against that plan with AI assistance, then checked by a validator that rejects anything without a single defensible answer, an explanation, or plausible wrong options. How we write questions sets out the whole process, and corrections are fixed in the bank and reach the site and the app the same day.

How you practise

This unit mixes 17 different question formats, so you are recalling and applying rather than recognising the same layout every time.

  • Build the sentence
  • Choose all that apply
  • Fact or fib
  • Fill the blank
  • Guess the number
  • Listen and choose
  • Match the pairs
  • Multiple choice
  • Odd one out
  • Picture question
  • Put in order
  • Sequence recall
  • Sort into groups
  • Spell it
  • Tap the pairs
  • True or false
  • Type the answer

Practise What is Physics?

118 questions across 20 steps. Start with step one and crawl at your own pace.

Play this unit

Read about What is Physics?

Explainers from our blog on what this unit covers. Each one ends with real questions from the bank.

More units in Physics

See all 18 units in Physics