Let's solve each question on the
Thermal Energy worksheet step by step, using the vocabulary provided:
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1. When there is an absence of energy, this is called
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Absolute zero
*Explanation:* Absolute zero is the theoretical temperature at which all molecular motion stops, meaning no thermal energy exists. It’s 0 Kelvin (−273.15°C or −459.67°F).
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2. Heat is transferred directly from one particle of matter to another by the process of
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Conduction
*Explanation:* Conduction is the transfer of heat through direct contact between particles in solids or stationary fluids.
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3. A circular flow of warmer fluid and cooler fluid is called a(n)
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Convection current
*Explanation:* In convection, warm fluid rises because it's less dense, cools, becomes denser, and sinks — creating a circular motion known as a convection current.
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4. To keep food warm or cool, coolers are made out of materials that are
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Insulators
*Explanation:* Insulators resist heat transfer, helping maintain the internal temperature of the cooler by slowing down heat exchange with the outside environment.
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5. __________ allow heat to flow easily
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Conductors
*Explanation:* Conductors, like metals, have free-moving electrons that transfer thermal energy efficiently.
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6. The total energy of all particles in an object is called
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Thermal energy
*Explanation:* Thermal energy is the sum of all kinetic and potential energies of the particles in a substance. It depends on mass, temperature, and phase.
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7. When particles spread out due to an increase of thermal energy, this is called
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Thermal expansion
*Explanation:* As particles gain thermal energy, they vibrate more and take up more space, causing materials to expand.
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8. Heat always flows from objects to objects.
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From hotter to colder
*Explanation:* Heat naturally moves from areas of higher temperature to areas of lower temperature until thermal equilibrium is reached.
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9. _________ is the transfer of energy by electromagnetic waves.
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Radiation
*Explanation:* Radiation transfers heat without requiring a medium (e.g., sunlight warming Earth). It occurs via infrared waves.
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10. Heat that is transferred by the movement of currents within a fluid is called
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Convection
*Explanation:* Convection involves the movement of heated fluid (liquid or gas), transferring heat through bulk motion.
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✔ Final Answers:
1.
Absolute zero
2.
Conduction
3.
Convection current
4.
Insulators
5.
Conductors
6.
Thermal energy
7.
Thermal expansion
8.
From hotter to colder
9.
Radiation
10.
Convection
These answers use the key vocabulary listed at the top of the page and align with fundamental concepts in thermal energy.
Parent Tip: Review the logic above to help your child master the concept of heat energy worksheet.
