1. Unit 4 Lesson 3 Thermal Energy and Heat
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2. Unit 4 Lesson 3 Thermal Energy and Heat
Florida Benchmarks
SC.7.N.1.1 Define a problem from the seventh grade curriculum, use appropriate reference materials to support scientific understanding, plan and carry out scientific investigations of various types, such as systematic observations or experiments, identify variables, collect and organize data, interpret data in charts, tables, and graphics, analyze information, make predictions, and defend conclusions.
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3. Unit 4 Lesson 3 Thermal Energy and Heat
Florida Benchmarks
SC.7.P.11.1 Recognize that adding heat to or removing heat from a system may result in a temperature change and possibly a change of state.
SC.7.P.11.4 Observe and describe that heat flows in predictable ways, moving from warmer objects to cooler ones until they reach the same temperature.
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4. Unit 4 Lesson 3 Thermal Energy and Heat
Florida Benchmarks
LA The student will organize information to show understanding (e.g., representing main ideas within text through charting, mapping, paraphrasing, summarizing, or comparing/contrasting).
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5. Thermal, Under Where? What is thermal energy?
Unit 4 Lesson 3 Thermal Energy and Heat
Thermal, Under Where?
What is thermal energy?
Thermal energy is the total kinetic energy of all particles in a substance.
Thermal energy is measured in joules (J).
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6. What is the difference between thermal energy and temperature?
Unit 4 Lesson 3 Thermal Energy and Heat
What is the difference between thermal energy and temperature?
Temperature is related to the average kinetic energy of particles.
Thermal energy is the total kinetic energy of all the particles.
For example, a glass of water can have the same temperature as a lake, but the lake has much more thermal energy because the lake contains many more water molecules.
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7. Unit 4 Lesson 3 Thermal Energy and Heat
Heat It Up!
What is heat?
Heat causes objects to feel hot or cold under the right conditions.
Heat is the energy transferred from an object at a higher temperature to an object at a lower temperature.
For example, energy in the form of heat flows from warm drinks to a bucket of ice.
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8. How is heat measured? Heat is measured in two ways.
Unit 4 Lesson 3 Thermal Energy and Heat
How is heat measured?
Heat is measured in two ways.
Heat is measured in calories (c).
One calorie is equal to the amount of energy needed to raise the temperature of 1 g of water by 1 °C.
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9. Unit 4 Lesson 3 Thermal Energy and Heat
How is heat measured?
Heat is also measured in joules (J) because heat is a measurement of energy.
One calorie is equal to 4.18 joules.
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10. Unit 4 Lesson 3 Thermal Energy and Heat
How is heat measured?
In nutrition, 1 calorie is actually 1 kilocalorie, or 1,000 calories.
To find out how many calories are in food, a sample of food is burned inside an instrument called a calorimeter.
The change in temperature in the calorimeter is used to calculate how much energy is released from the food sample.
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11. How is heat related to thermal energy?
Unit 4 Lesson 3 Thermal Energy and Heat
How is heat related to thermal energy?
When two objects at different temperatures come into contact, energy as heat flows from the warmer object to the cooler object.
When both objects are at the same temperature, no more energy as heat flows.
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12. How is heat related to thermal energy?
Unit 4 Lesson 3 Thermal Energy and Heat
How is heat related to thermal energy?
Even though two materials might have the same temperature, their thermal energies might be different.
Thermal energy depends on how many particles are present in the object.
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13. How can heat affect the state of an object?
Unit 4 Lesson 3 Thermal Energy and Heat
How can heat affect the state of an object?
The state of a substance depends on the speed of its particles.
Adding energy in the form of heat to a substance can result in a change of state.
Removing energy in the form of heat from a substance can result in a change of state.
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14. Keep Your Cool What is conduction?
Unit 4 Lesson 3 Thermal Energy and Heat
Keep Your Cool
What is conduction?
Energy as heat is transferred in three main ways.
Conduction is the transfer of energy as heat from one substance to another through direct contact.
As long as two objects are in contact, conduction continues until the temperatures of the objects are equal.
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15. Unit 4 Lesson 3 Thermal Energy and Heat
What is conduction?
A conductor is a material that transfers heat very well.
Metals are typically good conductors.
An insulator is a material that is a poor conductor of heat.
Wood, paper, and plastic foam are examples of good insulators.
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16. Unit 4 Lesson 3 Thermal Energy and Heat
What is convection?
Convection is the transfer of energy as heat by the movement of a liquid or gas.
Convection occurs when a cooler, denser mass of gas or liquid replaces a warmer, less dense mass of gas or liquid by pushing it upward.
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17. Unit 4 Lesson 3 Thermal Energy and Heat
What is convection?
When water is boiled, the water moves in roughly circular patterns because of convection.
This motion is due to density differences that result from temperature differences.
The motion is called a convection current.
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18. Unit 4 Lesson 3 Thermal Energy and Heat
What is radiation?
Radiation is the transfer of energy by electromagnetic waves.
All objects, including the sun and all living things, emit radiation.
When radiation is emitted from one object and is absorbed by another, the result is often a transfer of heat.
Radiation can travel through empty space.
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19. Practical Uses of Radiation
Unit 4 Lesson 3 Thermal Energy and Heat
Practical Uses of Radiation
A solar cooker is a device that cooks food using mirrors that concentrate radiation from the sun.
In parts of the world that are far from electricity and clean water, solar cookers are a useful way to sterilize water for drinking.
Many people like to use solar cookers because they do not release harmful emissions.
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