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Lesson 1 Energy Flow in Technological Systems

  Forms of Energy

When asked to define energy, it is usually easier to describe what energy can do.


C1.2 Oil pumpjack and power lines in a field
Energy does not have mass and cannot be seen, yet its presence and effect can be seen everywhere. Scientists saw the evidence of energy first and started to develop technologies that used energy before they were able to define energy (the definition for energy took a while). By the 1850s, scientists started to describe energy and realized that energy can take many forms.

So, what are the common types of energy? Where are some of the common places in nature and technology that the energy types are found?

Potential Energy


Energy can be stored and held ready to be used. This is known as potential energy, and it has the ability to be converted to different forms of energy and potential do work. Potential energy is energy due to relative position or condition. Common types of potential energy that we will look at in this course are chemical, solar, nuclear, and gravitational.

C1.3 Colourful fireworks
Energy can be stored in the chemical bonds of a compound. You already learned all about chemical energy in Units A and B of this course.

Chemical energy used in . . .
Natural Systems
Technological Systems
  • The food that we eat contains chemical energy; the energy is released in the digestive process and through cellular respiration.
  • Fossil fuels (coal, oil, natural gas) contain chemical energy; the energy is released when they are burned as a fuel.
  • Wood contains chemical energy; when it is burned, energy is released.
  • Batteries contain chemical energy; the energy is released when it produces electricity.
  • Vehicle air bags contain chemical energy; the bags are activated by a chemical reaction.
  • Heating packs contain chemical energy; when the pack is cracked, chemicals mix and create heat.
C1.4 The sun
Solar energy results from a reaction between hydrogen atoms in the star we call our sun. Nuclear energy is released, and the radiant energy travels to Earth where it is used and converted to other forms of energy.

Solar energy used in . . .
Natural Systems
Technological Systems
  • Plants use solar energy from the sun in the process of photosynthesis.
  • Heat energy from the sun, through the greenhouse effect, keeps Earth warm and habitable for life.
  • Development of solar panels has allowed humans to capture solar energy and convert it to electrical energy.
  • Solar energy can be used for cooking in solar ovens.
  • Solar energy can be used to heat homes through strategic placement of windows and solar heating tubes.

  Digging Deeper

C1.5 Summer sun
Solar energy is one of the oldest forms of energy known to be used by humans to our benefit. Some of the earliest known uses of solar energy date back to seventh century B.C. Go to the following link for more information. https://quick.adlc.ca/solar

Learn More

C1.6 Nuclear power generation station in Pickering, ON
Nuclear energy is potential energy stored within the nucleus of an atom. When atoms break apart (fission reaction) or join together (fusion reaction), tremendous amounts of energy are released.

Nuclear energy used in . . .
Natural Systems
Technological Systems
  • Fission reactions (when atoms break apart) do not normally occur in nature.
  • Fusion reactions (when atoms join together) occur in stars, such as the sun.
  • Nuclear weapons are fission bombs, also known as atomic bombs.
  • Uranium is the fuel used in nuclear power plants; fission nuclear reactions occur here.
C1.7 Wrecking ball
An object raised above Earth’s surface, whether it is an apple in a tree or a satellite orbiting Earth, has the potential to do work because of its position. Gravity wants to pull the object back down. How you can calculate the amount of gravitational potential energy an object has will be looked at further in Lesson 3, but generally, the higher and heavier the object, the more energy that is stored.

Gravitational potential energy used in . . .
Natural Systems
Technological Systems
  • A person riding down a hill does not need to pedal to stay in motion.
  • A crane releases a wrecking ball from a certain height to demolish a building.
  • Earth’s moon causes the tides of the ocean.
  • Hydropower uses water flowing downward due to gravity to spin a hydroelectric turbine and create electricity.
  • Water purifier systems use water flowing downward through filters due to gravity to purify the water.
  • Roller coasters and many amusement park rides use gravity to increase the thrill factor.

  Digging Deeper

©Wikimedia Commons
C1.9 Albert Einstein and Isaac Newton
Both Albert Einstein’s general theory of relativity and Sir Isaac Newton’s law of universal gravitation can be used to explain gravity. This is a great example of how observations of different scientists over many years can be combined to explain an observed phenomenon. Go to the following link for more information. https://quick.adlc.ca/gravity

Learn More

Kinetic Energy


Any object in motion has the ability to do work and possesses energy due to the motion. Simply, kinetic energy is the energy of motion. Common types of kinetic energy we will look at in this course are thermal and electric.

C1.10 Thermal hot spring at Cave and Basin, Banff National Park, AB
If you remember from the particle theory of matter, as a substance is heated up, its particles (molecules or atoms) begin to move faster and faster. Thermal energy is the amount of energy that a substance has as it relates to the amount of motion of the substance’s molecules or atoms. If the molecules or atoms have more motion, then the substance will have more thermal energy. Simply, as you increase or decrease the temperature of a substance, the amount of thermal energy increases or decreases.

Thermal energy used in . . .
Natural Systems
Technological Systems
  • Geothermal energy from the earth can be used directly to heat buildings or pools.
  • In the human body, the thermal energy released during cellular respiration is used to maintain a constant body temperature.
  • Decomposers in a compost pile release thermal energy during digestion, which then increases the rate of decomposition of organic matter.
  • Homes use thermal energy released from burning natural gas for heating and cooking.
  • Cogeneration power plants have been developed so that the thermal energy released in the combustion of fossil fuels is then used to generate electricity or heat buildings.
  • Thermal energy trapped in the surface water of oceans can be used in electricity generation.
C1.11 Illuminated fibre optics
Electrical energy is the work done when charges move. You studied protons (positive charges) and electrons (negative charges) in atoms of elements in Unit B. The energy produced when electrons move is electrical energy. There is a close relationship between electricity and magnetism. Electricity is a secondary energy source, which means it is usually generated from the conversion of a primary source of energy, such as fossil fuels, nuclear power, or renewable sources.

Electrical energy used in . . .
Natural Systems
Technological Systems
  • The discharge of a lightning bolt during a storm can reach the equivalent of more than 2 million car batteries.
  • Electric fish, such as eels and catfish, emit electrical discharges that can paralyze their prey or be used in defence.
  • Solar storms occur on the surface of the sun approximately every 11 years when masses of protons and electrons are released and can disrupt Earth’s magnetic field and effect Earth’s electrical power systems.
  • Electrical energy is used everywhere to power machines and devices.
  • Electrical energy can be used extensively for human entertainment and to make our lives easier.
  • Newer electrical technologies include electric car, and energy “smart” devices that increase efficiency.

  Read This

Please read pages 165 to 169 in your Science 10 textbook. Make sure you take notes on your readings to study from later. You should focus on the different types of energy and which natural and technological systems use the types of energy. Remember, if you have any questions or do not understand something, ask your teacher!

  Practice Questions

Complete the following practice questions to check your understanding of the concept you just learned about. Make sure you write complete answers to the practice questions in your notes. After you have checked your answers, make corrections to your responses (where necessary) to study from.

  1. Describe, in your own words, what energy is.
Your answer should be a variation of the following: Energy is the ability to do work. It can take many forms and can be converted from one form to another. Many different forms of energy are found on Earth and can be used to our advantage as humans!

  1. For each type of potential and kinetic energy described in this section, identify at least one natural system and one technological system that use the energy as its primary source.
Your answer can be a variation of the following, but here is a summary chart. Examples do not have to be those provided in the content above.

Type of Energy
Natural System
Technological System
Chemical
  • The food that we eat contains chemical energy; the energy is released in the digestive process and through cellular respiration.
  • Fossil fuels (coal, oil, natural gas) contain chemical energy; the energy is released when they are burned as a fuel.
  • Wood contains chemical energy; when it is burned, energy is released.
  • Batteries contain chemical energy; the energy is released when it produces electricity.
  • Vehicle air bags contain chemical energy; the bags are activated by a chemical reaction.
  • Heating packs contain chemical energy; when the pack is cracked, chemicals mix and create heat.
Solar
  • Plants use solar energy from the sun in the process of photosynthesis.
  • Heat energy from the sun, through the greenhouse effect, keeps Earth warm and habitable for life.
  • Development of solar panels has allowed humans to capture solar energy and convert it to electrical energy.
  • Solar energy can be used for cooking in solar ovens.
  • Solar energy can be used to heat homes through strategic placement of windows and solar heating tubes.
Nuclear
  • Fusion (when atoms join together) reactions occurs in stars, such as the sun.
  • Nuclear weapons are fission bombs, also known as atomic bombs.
  • Uranium is the fuel used in nuclear power plants; fission nuclear reactions occur here.
Gravitational
  • A person riding down a hill does not need to pedal to stay in motion.
  • A crane releases a wrecking ball from a certain height to demolish a building.
  • Earth’s moon causes tides of the ocean.
  • Hydropower uses water flowing downward due to gravity to spin a hydroelectric turbine and create electricity.
  • Water purifier systems use water flowing downward through filters due to gravity to purify water.
  • Roller coasters and many amusement park rides use gravity to increase the thrill factor.
Thermal
  • Geothermal energy from the earth can be used directly to heat buildings or pools.
  • In the human body, the thermal energy released during cellular respiration is used to maintain a constant body temperature.
  • Decomposers in a compost pile release thermal energy during digestion, which then increases the rate of decomposition of organic matter.
  • Homes use thermal energy released from burning natural gas for heating and cooking.
  • Cogeneration power plants have been developed so that the thermal energy released in combustion of fossil fuels is then used to generate electricity or heat buildings.
  • Thermal energy trapped in the surface water of oceans can be used in electricity generation.
Electrical
  • The discharge of a lightning bolt during a storm can reach the equivalent of more than 2 million car batteries.
  • Electric fish, such as eels and catfish, emit electrical discharges that can paralyze their prey or be used in defence.
  • Solar storms occur on the surface of the sun approximately every 11 years when masses of protons and electrons are released and can disrupt Earth’s magnetic field and effect Earth’s electrical power systems.
  • Electrical energy is used everywhere to power machines and devices.
  • Electrical energy can be used extensively for human entertainment and to make our lives easier.
  • Newer electrical technologies include electric cars and energy “smart” devices that increase efficiency.