Level 6 physics: Telecommunications 1
Communication is a cornerstone of modern society. In particular, developments in telecommunication are a milestone in human history.
Focus statements
- Physics is the study of the physical world; of matter and energy, and the relationship between them.
- The basis of communication is a transfer of energy.
- Telecommunication is the ability to effect change at a distance. By observing these changes, we can interpret meaning and information.
- Energy can travel great distances, particularly in the form of electro-magnetic energy, which can travel without a medium.
- Scientists have always been trying to develop and improve telecommunication.
- There are two kinds of wave; mechanical and electromagnetic:
- mechanical waves are the physical movement of matter
- electromagnetic waves are oscillating electric and magnetic fields. They do not need a medium through which to travel.
- Electricity flows in a circuit, and by controlling when the electric current flows in a circuit (which we can do easily, by breaking and connecting a circuit) we can affect change at a distance, and hence communicate.
- Electricity has a dual function – it can both communicate (effect change at a distance) and carry energy over long distances.
- Electricity is a form of energy. Voltage is the energy lost or gained per unit of charge.
- Electricity can move through material. A material that electric current can move through easily is called a conductor.If electrical current cannot move through a material easily, it is called an insulator.
- Resistance is the measure of how difficult it is to move current through a material.
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Possible activities for the NoS strand
The activities suggested here are linked to the various parts of the nature of science strand, to show how it can be embedded into the teaching programme.
Activities for understanding in science
- What scientific theories and discoveries led to the development of telephones?
- What discoveries lead to the major changes in telecommunications used so commonly today?
- How does digital transmission of information differ from older forms of transmission?
- What scientific ideas about waves have been used to transmit information using AM radio
- Discuss models of electricity and their limitations.
- Why is electricity is an ideal way of transmitting energy for use in society?
- Describe and explain how electromagnetic waves and their use have changed society over your lifetime.
- How and why is digital technology rather than analogue technology used for telecommunication in today’s society?
Activities for investigating science
- Investigate whether it is better to transmit “electricity” using thick wire or thin wires to reduce power loss.
- Design and carry out experiment(s) that will determine what (if any) frequencies of sound seem louder to us than other frequencies.
Activities for communicating in science
- Using the example of ocean waves, explain to an audience of year 9 students what the terms frequency, wavelength, and wave velocity mean.
- Compare the use of terms commonly used by the media when discussing electrical devices or electricity (for example, voltage, power, current) with the scientific view or definition of the same terms.
- Explain the scientific concepts underlying the following commonly used terms: digital transmission, analogue transmission, wireless technology.
Activities for participating and contributing
- What is the evidence for and against the health risks posed by cellphones, transmission lines, and microwaves?
- What are the scientific arguments for and against the construction and use of “American spy satellites” on Aotearoa New Zealand soil?
Discussion activities for participating and contributing
- Discuss the questions:
- What is communication?
- Is communication important? Why?
- Examine a historical context where the presence or absence of communication made a significant difference.
Possible investigative experiments
- Investigate the operation of a microphone.
- Investigate the operation of a speaker.
- Investigate the operation of a remote speaker/microphone (for example, cups on a string).
- Investigate the relationship between voltage and current (Ohm’s Law).
- Construct a simple (electrical) telecommunications device.
- Investigate communication methods for simple devices.
Community exercises
- Investigate a telecommunications device in operation, in the school or community.
- Interview a telecommunications expert from a local telecommunications company.
- Investigate the cost and feasibility of installing a school-wide telecommunications system (intercom) or expanding an existing one.
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Possible assessments
Learning could be assessed using a variety of standards – for example:
- AS90941 Science 1.2: Investigate the implications of electricity and magnetism for everyday life (4 credits, internal)
- AS90942 Science 1.3: Investigate the implications of wave behaviour for everyday life (4 credits, internal)
- AS90936 Physics 1.2: Demonstrate understanding of the physics of an application (building a device) (2 credits, internal)
- AS90937 Physics 1.3: Demonstrate understanding of aspects of electricity and magnetism (4 credits, external)
- AS90938 Physics 1.4: Demonstrate understanding of aspects of wave behaviour (4 credits, external)
Last updated December 14, 2012
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