Sonic Boomer - Dendrite.me

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Sonic Boomer - Dendrite.me
Speed of Sound
Lesson 1: Sonic Boomer
Over the course of two lessons, Key Stage 2 students are
introduced to the speed of sound and sonic booms. In lesson
1, students will learn that sound travels at a certain speed
and that it is possible for some objects to travel above this
speed. They will then learn about the sonic booms produced
by objects that are travelling above the speed of sound.
Students will carry out a practical to create a sonic boomer, a
folded piece of paper that can be used to create a sonic boom.
In lesson 2, students will investigate how changing the size of
the sonic boomer affects the volume of the sound it makes.
This will give students the opportunity to work scientifically as
they formulate predictions, plan their investigation and make
conclusions.
Speed of Sound
Speed of Sound
Teacher Information
BLOODHOUND Context & Topic Introduction
BLOODHOUND SSC is a car designed to achieve a speed of 1000mph. In
doing so, the car will be travelling above the speed of sound, which is
around 760mph (this figures varies depending on altitude and a number
of other factors).
At 1000mph, BLOODHOUND SSC will be supersonic i.e. travelling faster
than the speed of sound. When an object travels faster than the speed of
sound, the air molecules that are being pushed out of the way form highpressure waves (shockwaves). These high-pressure waves bunch up and
create a loud noise known as a sonic boom. A common misconception is
that hearing a sonic boom indicates that the object that has created it has
broken the sound barrier. In actual fact, the boom occurs continuously as
the object travels faster than the speed of sound.
There are a number of Physics websites that describe in greater detail
how shockwaves and sonic booms are generated. Although these sites are
too advanced for KS2 pupils, they provide great information if you would
like to extend your own knowledge around the topic:
 The Physics Classroom – The Doppler Effect and Shock Waves
 Phsylink.com – What is a sonic boom and how is it produced?
 Physics Central – Sonic Shock
A simple, paper ‘sonic boomer’ can be made to simulate the sound of a
sonic boom. The boomer is a sheet of paper that has been folded to
create two outer triangular pieces with a central flap of paper inside.
When the boomer is forced downwards in a rapid motion, air rushes into
the space between the triangular sections and the flap and forces the flap
outwards. Air molecules in front of the flap are compressed and a shock
wave is generated. The result is a sound like a whip being cracked or a
hand-clap; it is very similar to the sound of a sonic boom.
Speed of Sound
Curriculum Links
KS2 Science
Working scientifically:
 Asking relevant questions and using different types of scientific
enquiries to answer them.
 Setting up simple practical enquiries, comparative and fair tests.
 Making systematic and careful observations and, where appropriate,
taking accurate measurements using standard units.
 Gathering, recording, classifying and presenting data in a variety of
ways to help in answering questions.
 Recording findings using simple scientific language, drawings, labeled
diagrams, keys, bar charts and tables.
 Reporting on findings from enquiries, including oral and written
explanations, displays or presentations of results and conclusions.
 Using results to draw simple conclusions, make predictions for new
values, suggest improvements and raise further questions.
 Identifying differences, similarities or changes related to simple
scientific ideas and processes.
 Using straightforward scientific evidence to answer questions or to
support their findings.
Sound:
 Identify how sounds are made, associating them with something
vibrating.
 Recognise that vibrations from sounds travel through a medium to the
ear.
 Find patterns between the pitch of a sound and the features of the
object that produced it.
 Recognise that sound gets fainter as the distance from the sound
source increases.
Speed of Sound
Learning Objectives
The overall learning outcome for this lesson is that students will
understand that sound travels at a certain speed and that it is possible for
some objects to travel faster than this speed. Students will also do a
practical in which they must follow instructions to make a sonic boomer.
To achieve the outcome, students will be able to:
 State that it is possible for some objects to travel faster than the sound
that they make i.e. faster than the speed of sound.
 Give some examples of things that are able to travel faster than the
speed of sound.
 Assemble a sonic boomer, following a set of instructions.
Resources
Computer/laptop access
with a project &
screen/smart-board
Blown up balloon and
pin
Sheets of newspaper
1 per student plus
spares
‘Sonic boom
presentation’ resource
[hyperlink]
‘How to Make a Sonic
Boomer’ sheet
1 each or 1 between 2
‘True & False Cards’
resource
[hyperlink]
Key Vocabulary
Sound
Sonic boom
Speed of sound
Sonic boomer
Speed of Sound
Starter Activity
(5 - 10 minutes)
• Show the video footage of Thrust SSC making its record-breaking run in
1997. This can be found on slide 2 of the Sonic Boom Presentation.
• Students need to watch and listen carefully.
• Following the video, ask students the following questions:
 Could you see the car at the start of the video? At first, the car
cannot by seen. This is because it is very far away (it is beyond the
horizon/curvature of the Earth).
 Could you hear the car at the start of the video? No, the car
cannot be heard to begin with.
 When the car comes into sight, can you hear it? As the car gets
closer to the camera, it comes into sight and is travelling very fast.
However, for a few seconds it still cannot be heard.
 Why do you think this is happening? The car must be travelling
faster than the sound that it is making. i.e. it is travelling faster
than the speed of sound.
• The aim of this starter is for students to begin to gain an understanding
of sound having a speed and that it is possible for some objects to go
faster than this speed. This will come from observing Thrust SSC going
faster than its own speed.
Speed of Sound
Main Activity
Refer to ‘Sonic Boom Presentation’ resource [hyperlink].
Activity 1 – What is a sonic boom? (15 minutes)
 Teacher input – Show students the shortened clip of Thrust SSC (slide
4) and explain that the sound they can hear is a sonic boom.
 Use the presenter notes on Slide 4 to describe how a sonic boom is
produced.
 Discuss the other examples of vehicles that produce a sonic boom,
including BLOODHOUND SSC (slide 5).
 A diagram on slide 6 shows what shockwaves look like.
 An additional example of a sonic boom can be demonstrated by
popping a blown-up balloon with a pin. If this is not possible to
demonstrate, show the video of a balloon being popped (slides 7 & 8).
Activity 2 – Making a sonic boomer (15 minutes)
 Teacher input – Introduce the sonic boomer using the video on slide
9. Show students the how to make a sonic boomer using the video on
slide 23 and/or instructions given on slides 10-22. Students can also be
given a ‘How to Make a Sonic Boomer’ sheet, along with paper to make
a boomer.
 Student activity – Students should follow the instructions to make a
sonic boomer each.
 Once students have made their sonic boomer, they can try them out.
Activity 3 – Class discussion (10 minutes)
 Ask pupils a number of questions around their sonic boomers:
 Describe what happened. Did you see or hear anything? The flap in
the middle of the sonic boomer is forced out. As this happens,
there is a bang.
 How do you think this sound is being created? Air gets inside the
boomer, forcing the flap outwards. The air being pushed out of the
way bunches up and makes a loud sound.
Speed of Sound
 How might we be able to change the sound? By using a differentsized piece of paper or a different material e.g. card.
 Use slides 25-29 to explain how the sonic boomer works.
Plenary Activity
(10 minutes)
 True or false statements:
 Provide each student with a set of true and false cards.
Alternatively, provide them each with a mini-whiteboard to write
either true or false onto.
 Give students a number of statements to which they must either
respond true or false. These statements can also be used to ask
follow-on questions that can be answered via mini-whiteboards or
verbally.
 Statement: An object cannot travel faster than the speed of
sound. True or false?
 Answer: False – lots of things travel faster than the speed of
sound including fighter jets, space shuttles, Thrust SSC, etc.
 Question: What are some examples of things that can travel
faster than the speed of sound?
 Answer: Fighter jets, space shuttles, Concorde, Thrust SSC,
etc. When finished, BLOODHOUND SSC will also travel faster
than the speed of sound.
 Statement: When something is travelling faster than the
speed of sound, a loud sound is heard. True or false?
 Answer: True.
 Question: What is this loud sound called?
 Answer: A sonic boom.

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