🏃
🚄
⚡
✦ KNOW PRIMARY · AGES 6 TO 14 ✦

SCIENCE

Speed: how fast are things? Distance, time, and the race between a snail and a sunbeam.

📖 250 Topics 🆓 FREE + PRO ⏱️ 5 min per comic 🧠 Quiz included
📏
DISTANCE
How far
→
⏱️
TIME
How long
→
➗
DIVIDE
Speed
→
🐆
COMPARE
Cheetah vs you
→
🌅
HUGE
Light speed
⚡ SPEED: HOW FAST ARE THINGS?
TOPIC 07 · MOTION · DISTANCE · TIME · UNITS
PAGE 1 OF 5 · THE BIG IDEA: HOW FAST?
TWO INGREDIENTS
Comic illustration introducing the two ingredients of speed — distance and time — showing a race where the winner is determined by covering the most distance in the least time
SPEED = HOW QUICK THE TRIP
Speed answers: “If I go for a while, how much path do I pack per tick of the clock?” In clean symbols you often see v = d / t for a steady story: d is the distance you moved along the path, t is the time it took, and v is the speed (size only here). If you stop to tie your shoe, a single number may still be a useful average over the whole trip, even if you were not a robot the whole time.

Little-kid line: “Fast = lots of playground gobbled in a small snack of minutes.”
AVERAGE VS INSTANT (FIRST PASS)
Average speed = total distance ÷ total time (same path, whole trip). A car’s needle jumping around is closer to an instant read — we unpack that in later adventures. Units: if d is in metres and t in seconds, v is in metres per second (m/s). Kilometres per hour (km/h) is the road friend in many countries.
ZOOM!
BIKE BATTLE
Comic illustration of two children racing bikes over 100 metres, showing how the same distance in less time means a faster speed — time as the fair tiebreaker
🚴 The same 100 m in less time = faster. Time is the fair tie‑breaker for “who is quicker.”
RAIL PACE
Comic illustration of a high-speed train covering a vast distance per hour, showing how the same speed formula applies at much larger scales than a sprint or bike race
🚄 Long trains chew huge distance per hour — a different scale than a sprint, same idea.
PAGE 2 OF 5 · COMPARE THE WORLD
FAST CATS, FAST CARS
Comic illustration comparing a cheetah sprinting at about 120 km/h alongside a family car on a road, showing that both are distance-over-time stories and must use the same units to be compared fairly
SAME MATH, DIFFERENT ANIMALS
A cheetah in a full sprint, a family car on a long straight — both are “how fast in how much time” stories. 120 km/h (about) is a famous round cheetah number people throw around, and cars can match or beat that in safe legal places. You only win a fair compare if you are careful about the same units and what was measured (a short burst or a long cruise).
UNIT TRICK (HANDY)
To turn m/s into a rough km/h, multiply by about 3.6 (and divide the other way). Your teacher will show why with unit fractions.
WHOA!
SNAIL
Comic illustration of a snail moving slowly through a garden, representing the low end of the speed scale — a tiny distance covered per minute, perfect for showing that speed = distance divided by time at any scale
🐌 Tiny distance per minute — a sweet low speed for calm science.
SPRINT
Comic illustration of a runner crossing a finish line while a stopwatch measures the time, showing how a short measured track plus a timer gives a first real-world speed calculation
🏁 Short track + stopwatch = great lab for a first v guess.
ROAD
Comic illustration of a sports car on an open road showing a high km/h reading, representing the high end of everyday road speeds while noting that rules and safety are part of the real story
🏎️ Big km/h on the open road, but rules and safety are part of the real story.
PAGE 3 OF 5 · MEASURE WELL, TALK FAIR
JET TRAIL
Comic illustration of a rocket or jet aircraft leaving a trail across the sky, showing that planes and rockets operate on a much larger speed scale than bikes but follow the same distance-divided-by-time formula
✈️ Planes and rockets are not the same speed story as a bike, but the math shape of “distance per time” still fits.
STAY HONEST
Comic illustration of a hiker on a trail checking GPS speed on their phone, showing that GPS estimates speed by calculating small changes in position over short time intervals — still distance over time at heart
📱 GPS can estimate speed from small hops in position — still distance over time at heart, with extra tech around it.
TAPE + TIMER
Comic illustration of a student using a measuring tape and stopwatch to measure distance and time for a speed experiment, showing that accurate measurements of both sides of the equation are essential for a reliable result
MEASURE BOTH SIDES
A wobbly ruler and a forgotten start time make a wobbly v. Metre sticks, trundle wheels, phone timers, and race photo‑finish cameras are all in service of a clean d and a clean t. Write your units in homework — teachers love that, and future you will too.
TICK!
PAGE 4 OF 5 · BIG NUMBERS, CLEAR HEAD
LIGHT: THE ULTIMATE HIGH SCORE (IN A VACUUM)
Comic illustration showing the enormous scale of the speed of light — about 300,000 kilometres per second in a vacuum — dwarfing everyday speeds like sound, planes, and cheetahs on a visual scale
ABOUT 300,000 KILOMETRES EVERY SECOND
Visible light in empty space (and all massless “stuff” in that family) has a cosmic speed cap called c — a famous number near 3 × 10⁸ m/s in the books. Nothing with mass is meant to reach that in simple school relativity, but understanding the scale helps: your bike and a sunbeam are not a fair footrace. Sound in air is already “only” a few hundred m/s — fast for us, slow for light.
WOW!
AVERAGE
Comic illustration explaining average speed using a child's journey — total distance divided by total time — showing the result is fair even if they stopped for a juice break along the way
“Whole trip distance ÷ whole trip time” is a fair story even if you stopped for juice.”
SYMBOLS
Comic illustration of the speed formula v equals d divided by t written on a chalkboard, with reminders to match units — metres with seconds gives m/s, kilometres with hours gives km/h
v = d / t (steady or average read). Keep d, t, and v in matching units, or convert with care.
NOT YET
Comic illustration teasing the concept of velocity as speed with direction, shown as a vector arrow — a preview of a later topic that builds on the speed ideas covered here
Velocity is speed plus direction as a vector — a later page will steer there. Today: the size of how fast.
PAGE 5 OF 5 · TAKE IT WITH YOU
FROM SNAILS TO SUNBEAMS
Comic summary illustration showing four speed examples side by side — a snail, a sprinter, a car, and a beam of light — all on the same distance-over-time framework with vastly different numbers
ONE FRACTION, MANY LIVES
Whether you are timing a snack run, a bus route, or trying to feel how wild the number for light is, you are really playing with the same distance per time idea, with a calm measure habit and a wonder for scale. Next on the road: simple machines (how ramps and levers change the force side of a job) in Topic 8 — different comic, same love of clear thinking.
GO!
REMEMBER
Comic recap image of a cheetah and car side by side, used as a visual reminder that fair speed comparisons require the same units and careful measurement of both distance and time
🔑 KEY FACTS
v = d / t (steady or average) · m/s, km/h · Light in vacuum ≈ 3×10⁸ m/s (enormous) · Compare speeds with the same units · Velocity adds direction (later topic).
READ ALOUD
“Fast is not a feeling for a test — it is a how far in a how long. Bikes, trains, and beams of light all sit on the same kind of see‑saw, with very different numbers. Write your units, and the universe gets less confusing.”

High five! ✋
🧠 QUIZ TIME!
SPEED · 5 QUESTIONS
QUESTION 01
In a straight, steady run, the usual school link between speed v, distance d, and time t is —
QUESTION 02
If distance is in metres and time in seconds, the natural SI unit for speed is —
QUESTION 03
A trip is 120 km in 2 h of driving (steady story). The average speed is —
QUESTION 04
The speed of light in vacuum is a famous huge number — in rough round terms, which is the usual order?
QUESTION 05
A rough trick: multiply a speed in m/s by 3.6 to get a close value in km/h. So 10 m/s is about —
0/5
LOADING...
← TOPIC 06 📋 ALL TOPICS TOPIC 08 →