From smartphones to MRI scanners, satellites to solar panels — the technologies we rely on every day are built on our understanding of waves and motion. Australian scientists and engineers are turning wave physics into life-saving, world-changing innovations.
Think about your mobile phone. It uses invisible waves to send messages, browse the internet, and make calls — all without any visible connection.
Write down your answers before reading on:
Seeing inside the body with waves
Medical imaging has transformed healthcare by letting doctors see inside the body without surgery.
Australian example: Australian scientists at CSIRO developed key software algorithms used in medical imaging worldwide, improving image quality and reducing scan times.
Finding your way and staying connected
GPS and communication technologies rely on electromagnetic waves:
Australian example: The Royal Australian Air Force uses advanced radar systems for air defence, and Australia's satellite ground stations support global navigation networks.
Moving people and goods efficiently
Understanding motion and forces has revolutionised transport:
Australian example: Australia is testing autonomous mining trucks in Western Australia's Pilbara region, and electric bus trials are running in major cities.
Powering the future with waves and motion
Wave and motion science is central to renewable energy:
Australian example: Australia leads the world in per-capita solar panel installation. The Snowy Hydro scheme is one of the largest hydroelectric projects in the Southern Hemisphere. CSIRO is developing wave energy technology for Australia's vast coastline.
"MRI uses X-rays to create images." No — MRI uses magnetic fields and radio waves, not X-rays. X-rays are used in CT scans and standard X-ray imaging.
"GPS satellites track your phone." Not exactly — your phone receives signals from satellites and calculates its own position. The satellites do not track individual phones.
CSIRO and medical imaging: The Commonwealth Scientific and Industrial Research Organisation (CSIRO) has developed world-leading image processing software used in MRI and CT scanners globally. Australian researchers continue to push the boundaries of what medical imaging can detect and diagnose.
The Square Kilometre Array: Australia and South Africa are jointly building the world's largest radio telescope. Located in Western Australia, the SKA will detect radio waves from the dawn of the universe, requiring extraordinary engineering to manage vast amounts of data and interference.
Smart transport in Australian cities: Sydney and Melbourne are deploying smart traffic management systems that use sensors and real-time motion data to optimise traffic flow. The Sydney Metro is Australia's biggest public transport project, using automated train technology guided by advanced motion sensing systems.
1. Which technology uses high-frequency sound waves to create images of soft tissues in the body?
2. GPS calculates position by measuring:
3. Which renewable energy technology converts light (electromagnetic waves) directly into electricity?
4. Anti-lock braking systems (ABS) are an application of which scientific principle?
5. The Square Kilometre Array (SKA) being built in Western Australia will detect:
1. Describe how understanding wave properties has led to the development of three different medical imaging technologies. Include the wave type used by each. 4 MARKS
2. Explain why different applications (medical imaging, communication, navigation) use different parts of the electromagnetic spectrum. Use specific examples. 4 MARKS
3. Evaluate how wave and motion science has contributed to the development of renewable energy technologies in Australia. Discuss at least two technologies. 4 MARKS
Go back to your Think First answer. Has your understanding changed?
C — Ultrasound uses high-frequency sound waves (2-18 MHz) to create images of soft tissues, muscles, and organs.
B — GPS measures the time radio signals take to travel from multiple satellites to the receiver. Using the speed of light and triangulation, the receiver calculates its exact position.
B — Solar panels use the photoelectric effect to convert light (electromagnetic waves) directly into electrical energy.
B — ABS uses sensors to detect when wheels are about to lock up (violating the principles of controlled braking governed by Newton's laws), then pulses the brakes to maintain traction and steering control.
B — The SKA is a radio telescope that will detect radio waves from the early universe, providing unprecedented detail about the formation of the first stars and galaxies.
Model answer: Understanding wave properties has enabled three key medical imaging technologies. X-rays use high-energy electromagnetic waves that penetrate soft tissue but are absorbed by bone, creating images of skeletal structures. Ultrasound uses high-frequency sound waves (2-18 MHz) that reflect off tissue boundaries, creating real-time images of soft tissues and organs without ionising radiation. MRI uses radio waves combined with strong magnetic fields to excite hydrogen atoms in the body; when these atoms relax, they emit radio signals that are detected and processed into detailed 3D images of soft tissues.
Model answer: Different applications use different parts of the electromagnetic spectrum because each wavelength range has unique properties. Medical X-rays use high-energy, short-wavelength radiation because it penetrates soft tissue but is absorbed by denser bone, creating contrast. Communication technologies (mobile phones, WiFi) use microwaves and radio waves because these longer wavelengths can travel long distances, penetrate buildings, and carry large amounts of data. GPS uses precise radio signals from satellites because radio waves travel at the speed of light and can be measured with extreme timing accuracy for position calculation.
Model answer: Wave and motion science has been fundamental to Australian renewable energy. Solar panel technology relies on understanding the photoelectric effect — how photons (light waves) transfer energy to electrons in semiconductor materials. Australia's high solar irradiance makes solar power highly effective, and Australian researchers at CSIRO have improved solar cell efficiency. Wind energy depends on understanding fluid dynamics and rotational motion — wind turbines convert the kinetic energy of moving air into rotational motion that drives generators. Australia's coastal and inland wind resources are significant, and wind farms now generate substantial portions of electricity in states like South Australia and Victoria.
Design and build wave-powered technologies! Choose the right wave properties for each application in this engineering design challenge.
Tick when you have finished all activities and checked your answers.