Physics Lesson 4 — Waves

Wave Properties & Definitions

Spec 3.1 · 3.3 · 3.4

Learning Objectives:

3.1 – Use the units: degree (°), hertz (Hz), metre (m), metre/second (m/s), second (s).
3.3 – Know the definitions of amplitude, wavefront, frequency, wavelength and period.
3.4 – Know that waves transfer energy and information without transferring matter.

Navigation: Arrow Keys or Spacebar

🖨️ Pupil Packs

⏱️ 40-Minute Pacing Guide

Core path (40 min): Arrival → Starter → I Do 1 → We Do 1 → I Do 2 → We Do 2 → Independent → Exit Ticket

FLEX slides (I Do 3 + We Do 3): Use if time allows, or as next-lesson warm-up. Marked with 🟠 FLEX badge.

⏱️ 4 min

Arrival Task

Arrival Task – What Do You Already Know?

Instructions: Answer from memory. This is a new topic — do your best!

1. 🟢

Name two examples of waves you have seen or heard.

Any from: water waves, sound waves, light, radio waves, microwaves, Mexican waves, etc.

2. 🟢

If you drop a stone into a pond, what happens to the water?

Ripples (waves) spread outwards in circles from where the stone entered.

3. 🟢

Does a duck sitting on a pond move across the water when a wave passes? Or does it bob up and down?

It bobs up and down — the duck doesn't travel with the wave. The wave passes under it.

4. Lead-in 🌊

If the duck doesn't move forward, what does the wave carry from one place to another?

Energy (and information). The wave carries energy outwards but the water/matter stays in roughly the same place.

1. 🟠

Name three different types of wave.

Water waves, sound waves, light waves, radio waves, seismic waves, microwaves, etc.

2. 🟠

What do you think the word "frequency" means in everyday English? How might it apply to waves?

Frequency means how often something happens. For waves, it means how many waves pass a point each second.

3. 🟠

When you shout across a field, your friend hears you. Did any air travel from your mouth to their ear, or just the sound?

Just the sound (energy). The air particles vibrate back and forth but don't travel across the field.

4. Lead-in 🌊

If waves don't move matter, what two things do they transfer from one place to another?

Energy and information.

1. 🔵

Explain, using a water wave example, what the terms "crest" and "trough" might mean.

Crest = the highest point of a wave. Trough = the lowest point.

2. 🔵

A wave has a frequency of 5 Hz. What does this tell you?

5 complete waves pass a point every second. Hz means "per second".

3. 🔵

Earthquakes send seismic waves through the Earth. Do the rocks travel from the earthquake to your house, or just the energy?

Just the energy. The rocks vibrate in place — the wave transfers energy through them but the matter doesn't travel.

4. Lead-in 🌊

Radio stations broadcast at different frequencies. Why do you think frequency is measured in hertz (Hz) rather than metres?

Frequency measures how many waves per second (a time-based measurement), not a distance. Metres measure wavelength (distance). Different quantities need different units.

⏱️ 3 min

Starter

Starter: Where Have You Seen Waves? 🌊

Instructions: No science knowledge needed! Just think about your everyday life. In your book, answer the 3 questions below. 3 minutes.

📝 Think & Write

1. List 3 places you've seen waves in real life. (Think: beach, pond, music speaker, microwave…)

2. Draw a simple picture of a wave — what shape is it?

3. When a wave moves, what do you think actually travels — the water itself, or just the energy?

💡 Need ideas? Ocean, ripples in a puddle, sound from a speaker, the wiggly line on a heart monitor, the mexican wave at football…

🖼️ Can you spot waves here?

These are all waves! They move energy but not matter.

💡 Did You Know?

The loudest sound ever recorded was the 1883 Krakatoa eruption — heard 4,800 km away. That's the same wave physics you're about to study!

⏱️ 4 min

I Do

I Do: Wave Definitions (3.3)

Key Idea: You must know 5 definitions: amplitude, wavefront, frequency, wavelength, period.

📐 The 5 Key Definitions

Amplitude — the maximum displacement from the rest position. How "tall" the wave is.

Wavelength (λ) — the distance from one point on a wave to the same point on the next wave (e.g. crest to crest). Measured in metres (m).

Frequency (f) — the number of complete waves passing a point per second. Measured in hertz (Hz).

Period (T) — the time taken for one complete wave to pass. Measured in seconds (s). T = 1/f.

Wavefront — an imaginary line joining all the points on a wave that are at the same stage of vibration (e.g. all the crests).

Anatomy of a Wave

🌍 Why This Matters

Music producers adjust amplitude (volume) and frequency (pitch). Doctors use ultrasound waves to see babies. Surfers read wavelengths to catch the perfect wave. Understanding wave properties explains sound, light, Wi-Fi, earthquakes, and even how your microwave heats food.

💡 Memory tricks:
Amplitude = how Amazing (tall) the wave is
Frequency = how Fast they come (per second)
λ (lambda) = Length of one wave

🔑 Keywords to Know

Amplitude	How TALL the wave is — maximum displacement from rest.
Wavelength (λ)	Distance from one crest to the next. Measured in metres.
Frequency (f)	How many waves per second. Measured in hertz (Hz).
Period (T)	Time for ONE complete wave. T = 1/f.

⏱️ 5 min

We Do

We Do: Label the Wave 🏷️

Instructions: Select a label, then click the correct slot on the wave diagram. Match all 7!

👥 Think-Pair-Share: Try it yourself → discuss with your partner → agree on the answer.

Crest Trough Amplitude Wavelength Rest position Hertz (Hz) Metres (m)

Parts of a Wave

The highest point is called the ?

The lowest point is called the ?

The height from rest to crest is the ?

The distance from one crest to the next is the ?

The flat line the wave oscillates around is the ?

Units

Frequency is measured in ?

Wavelength is measured in ?

Matched: 0 / 7

⏱️ 4 min

I Do

I Do: Waves Transfer Energy, Not Matter (3.4)

Key Idea: Waves transfer energy and information from one place to another without transferring matter.

🌊 The Duck Test

Drop a stone in a pond. Waves ripple outward. But a floating duck just bobs up and down — it doesn't travel with the wave.

This proves the water (matter) stays put. Only the energy moves outward.

📡 What DO Waves Carry?

✅ Energy — a tsunami carries massive energy from an earthquake across an entire ocean.

✅ Information — radio waves carry music, Wi-Fi carries data, light lets you see.

❌ Matter — the particles vibrate in place but don't travel with the wave.

Energy Travels, Matter Doesn't

🌟 Think Deeper: A Mexican wave in a stadium is a great example — the pattern moves around the stadium but the people (matter) stay in their seats. They just stand up and sit down.

⏱️ 5 min

We Do

We Do: Match the Definition 🧩

Instructions: Click a term on the left, then click its matching definition on the right. Get all 5!

👥 Think-Pair-Share: Try it yourself → discuss with your partner → agree on the answer.

Terms (click first)

Amplitude

Wavelength (λ)

Frequency (f)

Period (T)

Wavefront

Definitions (then click match)

Time for one complete wave to pass a point (seconds)

Maximum displacement from the rest position

Line joining points at the same stage of vibration

Number of complete waves per second (Hz)

Distance from one point to the same point on the next wave (m)

Matched: 0 / 5

⏱️ 4 min · FLEX

I Do

I Do: Period & Frequency — The Link

Key Idea: Period and frequency are inverses. T = 1/f and f = 1/T.

🔄 The Relationship

T = 1 ÷ f f = 1 ÷ T

If f = 5 Hz → 5 waves per second → each wave takes T = 1 ÷ 5 = 0.2 s

If T = 0.02 s → each wave takes 0.02 s → f = 1 ÷ 0.02 = 50 Hz

📋 Summary — All 5 Quantities

Quantity	Symbol	Unit	Measures
Amplitude	A	m	Height of wave
Wavelength	λ	m	Length of one wave
Frequency	f	Hz	Waves per second
Period	T	s	Time per wave
Wave speed	v	m/s	How fast wave travels

Frequency vs Period

🌟 Exam Tip: If they ask "what happens to the period when frequency increases?" — the answer is always: period decreases. They are inversely proportional.

⏱️ 5 min · FLEX

We Do

We Do: Energy or Matter? ✅❌

Instructions: For each scenario, decide: does the wave transfer matter, or just energy/information?

👥 Think-Pair-Share: Try it yourself → discuss with your partner → agree on the answer.

1. 🌊 A tsunami crosses the Pacific Ocean.

Does the water from Japan arrive in California?

2. 📻 A radio signal reaches your car.

Does any matter move from the radio tower to your car?

3. 🏟️ A Mexican wave goes around a stadium.

Do the fans travel around the stadium?

4. 🔊 You shout across a playground.

Do air particles from your mouth reach your friend's ear?

5. 🌍 An earthquake sends seismic waves 1000 km.

Do the rocks travel 1000 km?

Correct: 0 / 5 🌊

⏱️ 8 min

Independent Work

Instructions: Complete the tasks in your printed pack independently.

📝 Your Pack Contains:

Section A: Multiple Choice (4 questions)

Section B: Short Answer — label a wave, match units

Section C: Long Answer — explain energy transfer

Section D: Exam-Style Question

Need help? Check the Scaffolding Sheet for definitions and the labelled wave diagram.

📝 Exam Command Words:
State = write a fact, no explanation needed.
Calculate = show the formula, substitute, get the answer + unit.
Explain = say what happens AND why (use "because").
Describe = say what happens step by step (no "why" needed).

🏆 Success Criteria

Foundation (Grades U–1): I can name the 5 wave quantities, label a wave diagram, and state that waves transfer energy not matter.

Middle (Grades 1–2): I can define all 5 quantities with units, explain the duck test, and link period to frequency.

Higher (Grades 3–5): I can explain T = 1/f, apply energy transfer to real-world scenarios, and distinguish wavefronts from wavelength.

✅ Tick as you go — Success checklist

I can define amplitude, wavelength, frequency, period

I know waves transfer energy, not matter

I know the unit of frequency (Hz)

I can use T = 1/f (Middle/Higher)

⏱️ 3 min

Exit Ticket

Exit Ticket – Check Your Learning

Instructions: Answer independently. No notes.

🟢 I'm confident — I could teach this

🟡 Getting there — need more practice

🔴 I'm stuck — I need help

1) What is the amplitude of a wave?

The maximum displacement from the rest position (height of the wave).

2) What unit is frequency measured in?

Hertz (Hz).

3) Do waves transfer energy or matter?

Energy (and information). Not matter.

Knowledge Organiser: Wave Properties (L4)

How to use: Read this before starting. Refer back during independent work. Cover it up for the exit ticket — that tests what you actually remember!

Concept	Details
Amplitude	Maximum displacement from rest position. Measured in metres (m).
Wavelength (λ)	Distance from one point to same point on next wave (crest→crest). Metres (m).
Frequency (f)	Number of complete waves per second. Hertz (Hz).
Period (T)	Time for one complete wave. Seconds (s). T = 1/f.
Wavefront	Line joining points at the same stage of vibration.
Wave speed (v)	How fast the wave travels. Metres per second (m/s).
Energy transfer	Waves transfer energy and information WITHOUT transferring matter.
T and f	Inversely related: T = 1/f. High frequency = short period.
Crest & Trough	Crest = highest point. Trough = lowest point.

🧠 Memory Tricks

Amplitude = how Amazing (tall) the wave is.

Frequency = how Fast they come (per second).

λ (lambda) looks like an upside-down V = the Valley between two crests = wavelength.

Waves transfer energy, not matter = "The duck bobs but doesn't travel!"

Arrival Task – Foundation (U–1) 🟢

1. Name two examples of waves you have seen or heard.

2. If you drop a stone in a pond, what happens?

3. Does a duck move across the pond when a wave passes, or bob up and down?

4. If the duck doesn't move forward, what does the wave carry?

Arrival Task – Middle (1–2) 🟠

1. Name three different types of wave.

2. What does "frequency" mean? How might it apply to waves?

3. When you shout across a field, does air travel to your friend or just sound?

4. If waves don't move matter, what two things do they transfer?

Arrival Task – Higher (3–5) 🔵

1. Explain what "crest" and "trough" mean using a water wave example.

2. A wave has a frequency of 5 Hz. What does this tell you?

3. Do the rocks travel from an earthquake to your house, or just the energy?

4. Why is frequency measured in Hz not metres?

Starter: Units Match-Up

Quantity	Unit	Symbol
Frequency
Wavelength
Wave speed
Period
Angle

Word bank: Hz (hertz) · m (metre) · m/s · s (second) · ° (degree)

We Do Worksheet

Part A: Label the Wave

Write the correct label next to each description.

1. Highest point: _________ 2. Lowest point: _________ 3. Height from rest to crest: _________ 4. Distance crest to crest: _________ 5. Flat line wave oscillates around: _________

Word bank: Crest · Trough · Amplitude · Wavelength · Rest position

Part B: Match Term to Definition

Term	Definition
Amplitude
Wavelength
Frequency
Period
Wavefront

Part C: Energy or Matter?

For each, write "Energy" or "Matter".

1. A tsunami crosses an ocean. What travels? _________

2. A radio signal reaches your car. What transfers? _________

3. Sound travels from a speaker to your ear. What moves? _________

Scaffolding Sheet

Wave Definitions

Term	Definition	Unit
Amplitude	Max displacement from rest	m
Wavelength (λ)	Distance: one point → same point on next wave	m
Frequency (f)	Waves per second	Hz
Period (T)	Time for 1 wave. T = 1/f	s
Wavefront	Line joining points at same vibration stage	—

Key Rule

Waves transfer energy and information without transferring matter.

The particles vibrate in place — only the pattern (energy) moves forward.

Independent Work – Foundation (Grades U–1)

You've got this! Use your scaffolding sheet. Write the formula first every time. Show your working — even partial working earns marks.

Section A: Multiple Choice

1. The highest point of a wave is called the… [ ] Trough [ ] Crest [ ] Amplitude

2. Frequency is measured in… [ ] Metres [ ] Hertz [ ] Seconds

3. Waves transfer… [ ] Matter [ ] Energy [ ] Atoms

4. The time for one complete wave is called the… [ ] Wavelength [ ] Amplitude [ ] Period

Section B: Short Answer

5. Label this wave: write "Crest", "Trough", "Amplitude", "Wavelength" and "Rest position" on the diagram.

[Wave diagram — draw your own and label it]

6. State what unit wavelength is measured in.

7. A duck sits on a pond. A wave passes under it. Describe what happens to the duck.

Section C: Long Answer (Grade 2 Challenge — scaffolded)

8. (4 marks) Complete the sentences about waves and energy.

When you drop a stone in a pond, _________________________ spread outward. [1 mark]

A duck floating on the pond does not travel with the wave. It just _________________________ . [1 mark]

This shows that waves transfer _________________________ but not _________________________ . [2 marks]

Section D: Exam-Style

9. (3 marks) Define the following wave properties:

(a) Amplitude [1 mark]

(b) Wavelength [1 mark]

Independent Work – Middle (Grades 1–2)

Push yourself! Show full working for every calculation. Section D is your Grade 3 stretch — give it your best shot.

Section A: Multiple Choice & Recall

1. Which quantity has the unit hertz? [ ] Wavelength [ ] Frequency [ ] Period

2. T = 1/f. If f = 10 Hz, T = … [ ] 10 s [ ] 0.1 s [ ] 100 s

3. Define amplitude.

4. What is a wavefront?

Section B: Application

5. Complete the table:

Frequency (Hz)	Period (s)
2
5
50
	0.01

6. Explain, using a named example, how a wave transfers information. [2 marks]

Section C: Long Answer

7. (4 marks) A student says "when you shout across a room, the air from your mouth reaches the listener." Explain why this is wrong. [4 marks]

Section D: Exam-Style (Grade 3 Stretch)

8. (5 marks) A student observes water waves in a ripple tank. She counts 20 complete waves passing a point in 10 seconds. The distance between adjacent crests is 0.04 m.

(a) Calculate the frequency. [2 marks]

(b) State the wavelength. [1 mark]

Independent Work – Higher (Grades 3–5)

Aim high! Full sentences for explanations. Section D includes Grade 5 challenges — these go beyond the basics. Show the examiner you can reason, not just calculate.

Section A: Recall

1. Define wavelength and state its unit. [2 marks]

2. Distinguish between a wavefront and a wavelength. [2 marks]

3. Explain the relationship between period and frequency. [2 marks]

Section B: Application

4. Complete the table and show working:

f (Hz)	T (s)	Working
250
	0.002
50000

5. A seismic wave travels 500 km through the Earth. Explain why the rocks at the destination did not come from the epicentre. [3 marks]

Section C: Long Answer

6. (5 marks) Compare how a Mexican wave in a stadium and a water wave in the ocean both demonstrate the principle that waves transfer energy without transferring matter. [5 marks]

Section D: Exam-Style (includes Grade 5 Challenge)

7. (6 marks) A student uses a ripple tank. She measures the wavelength as 0.02 m and counts 40 waves passing a point in 8 seconds.

(a) Calculate the frequency. [2 marks]

(b) Calculate the period. [2 marks]

(c) The student increases the frequency but the wave speed stays the same. Explain what happens to the wavelength. [2 marks]

Exit Ticket – Foundation (U–1)

Name: _________________________ Date: _____________

1) What is the amplitude?

2) What unit is frequency measured in?

3) Do waves transfer energy or matter?

Exit Ticket – Middle (1–2)

1) Define wavelength.

2) f = 4 Hz. Calculate T.

3) Explain why a duck doesn't move forward when a wave passes.

Exit Ticket – Higher (3–5)

1) Distinguish between wavefront and wavelength.

2) T = 0.005 s. Calculate f.

3) How can a tsunami destroy buildings 10,000 km away without the water travelling that far?

Wave Properties & Definitions

🖨️ Pupil Packs

⏱️ 40-Minute Pacing Guide

Arrival Task – What Do You Already Know?

1. 🟢

2. 🟢

3. 🟢

4. Lead-in 🌊

1. 🟠

2. 🟠

3. 🟠

4. Lead-in 🌊

1. 🔵

2. 🔵

3. 🔵

4. Lead-in 🌊

Starter: Where Have You Seen Waves? 🌊

📝 Think & Write

🖼️ Can you spot waves here?

💡 Did You Know?

I Do: Wave Definitions (3.3)

📐 The 5 Key Definitions

Anatomy of a Wave

🌍 Why This Matters

🔑 Keywords to Know

We Do: Label the Wave 🏷️

Parts of a Wave

Units

I Do: Waves Transfer Energy, Not Matter (3.4)

🌊 The Duck Test

📡 What DO Waves Carry?

Energy Travels, Matter Doesn't

We Do: Match the Definition 🧩

I Do: Period & Frequency — The Link

🔄 The Relationship

📋 Summary — All 5 Quantities

Frequency vs Period

We Do: Energy or Matter? ✅❌

Independent Work

📝 Your Pack Contains:

🏆 Success Criteria

✅ Tick as you go — Success checklist

Exit Ticket – Check Your Learning

Knowledge Organiser: Wave Properties (L4)

🧠 Memory Tricks

Arrival Task – Foundation (U–1) 🟢

Arrival Task – Middle (1–2) 🟠

Arrival Task – Higher (3–5) 🔵

Starter: Units Match-Up

We Do Worksheet

Part A: Label the Wave

Part B: Match Term to Definition

Part C: Energy or Matter?

Scaffolding Sheet

Wave Definitions

Key Rule

Independent Work – Foundation (Grades U–1)

Section A: Multiple Choice

Section B: Short Answer

Section C: Long Answer (Grade 2 Challenge — scaffolded)

Section D: Exam-Style

Independent Work – Middle (Grades 1–2)

Section A: Multiple Choice & Recall

Section B: Application

Section C: Long Answer

Section D: Exam-Style (Grade 3 Stretch)

Independent Work – Higher (Grades 3–5)

Section A: Recall

Section B: Application

Section C: Long Answer

Section D: Exam-Style (includes Grade 5 Challenge)

Exit Ticket – Foundation (U–1)

Exit Ticket – Middle (1–2)

Exit Ticket – Higher (3–5)

We Do – Class Evidence

📋 Exam Technique — Every Mark Counts!