Set Design Requirements - Middle School Physical Science
Card 1 of 25
Identify whether this requirement is a criterion or constraint: "Keep water between $20,^{\circ}\text{C}$ and $25,^{\circ}\text{C}$."
Identify whether this requirement is a criterion or constraint: "Keep water between $20,^{\circ}\text{C}$ and $25,^{\circ}\text{C}$."
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Criterion. Temperature ranges are performance targets to achieve.
Criterion. Temperature ranges are performance targets to achieve.
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What is the best general testable form for a thermal-control criterion: qualitative or quantitative?
What is the best general testable form for a thermal-control criterion: qualitative or quantitative?
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Quantitative (measurable with numbers and units). Numbers enable precise testing and clear pass/fail decisions.
Quantitative (measurable with numbers and units). Numbers enable precise testing and clear pass/fail decisions.
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Which requirement is more objective for a criterion: "works well" or "limits temperature drop to $\leq 2,^{\circ}\text{C}$ in $10,\text{min}$"?
Which requirement is more objective for a criterion: "works well" or "limits temperature drop to $\leq 2,^{\circ}\text{C}$ in $10,\text{min}$"?
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"Limits temperature drop to $\leq 2,^{\circ}\text{C}$ in $10,\text{min}$". Specific numbers allow objective testing and comparison.
"Limits temperature drop to $\leq 2,^{\circ}\text{C}$ in $10,\text{min}$". Specific numbers allow objective testing and comparison.
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Which heat transfer mechanism is mainly reduced by wrapping an object in aluminum foil with the shiny side out?
Which heat transfer mechanism is mainly reduced by wrapping an object in aluminum foil with the shiny side out?
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Radiation. Shiny foil reflects infrared electromagnetic waves.
Radiation. Shiny foil reflects infrared electromagnetic waves.
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Which heat transfer mechanism is mainly reduced by adding a lid to prevent warm air from rising away?
Which heat transfer mechanism is mainly reduced by adding a lid to prevent warm air from rising away?
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Convection. Lids stop heated air from escaping upward.
Convection. Lids stop heated air from escaping upward.
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Which heat transfer mechanism is mainly reduced by adding a foam layer between two solids?
Which heat transfer mechanism is mainly reduced by adding a foam layer between two solids?
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Conduction. Foam blocks direct particle-to-particle heat transfer.
Conduction. Foam blocks direct particle-to-particle heat transfer.
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Identify whether this requirement is a criterion or constraint: "Must fit inside a box of volume less than $1,\text{L}$."
Identify whether this requirement is a criterion or constraint: "Must fit inside a box of volume less than $1,\text{L}$."
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Constraint. Size limits restrict design options.
Constraint. Size limits restrict design options.
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Identify whether this requirement is a criterion or constraint: "The device must cost under $\$10$."
Identify whether this requirement is a criterion or constraint: "The device must cost under $\$10$."
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Constraint. Cost limits are restrictions, not performance goals.
Constraint. Cost limits are restrictions, not performance goals.
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Which term names a measurable requirement like "keep contents above $50,^{\circ}\text{C}$"?
Which term names a measurable requirement like "keep contents above $50,^{\circ}\text{C}$"?
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Criterion. Criteria specify performance targets to meet.
Criterion. Criteria specify performance targets to meet.
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What is the meaning of a design criterion when building a device to control thermal energy transfer?
What is the meaning of a design criterion when building a device to control thermal energy transfer?
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A desired feature or performance goal the device must achieve. Criteria define what the device should accomplish, not what limits it.
A desired feature or performance goal the device must achieve. Criteria define what the device should accomplish, not what limits it.
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Which surface property best increases heat transfer by radiation when cooling is desired?
Which surface property best increases heat transfer by radiation when cooling is desired?
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High emissivity, dark and matte surface. Dark surfaces absorb and emit radiation efficiently.
High emissivity, dark and matte surface. Dark surfaces absorb and emit radiation efficiently.
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Which surface property best reduces heat transfer by radiation from a hot object?
Which surface property best reduces heat transfer by radiation from a hot object?
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Low emissivity, shiny or reflective surface. Reflective surfaces bounce electromagnetic waves away.
Low emissivity, shiny or reflective surface. Reflective surfaces bounce electromagnetic waves away.
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Which design feature most directly reduces heat transfer by convection in a container?
Which design feature most directly reduces heat transfer by convection in a container?
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Sealing to stop fluid motion and air exchange. Prevents warm air currents from carrying heat away.
Sealing to stop fluid motion and air exchange. Prevents warm air currents from carrying heat away.
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Which material property should be prioritized to reduce heat transfer by conduction?
Which material property should be prioritized to reduce heat transfer by conduction?
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Low thermal conductivity (use an insulator). Insulators have poor particle-to-particle energy transfer.
Low thermal conductivity (use an insulator). Insulators have poor particle-to-particle energy transfer.
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What is radiation in thermal energy transfer, in one accurate sentence?
What is radiation in thermal energy transfer, in one accurate sentence?
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Transfer of thermal energy by electromagnetic waves. No medium needed; energy travels as infrared waves.
Transfer of thermal energy by electromagnetic waves. No medium needed; energy travels as infrared waves.
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What is convection in thermal energy transfer, in one accurate sentence?
What is convection in thermal energy transfer, in one accurate sentence?
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Transfer of thermal energy by motion of a fluid (liquid or gas). Heated fluid rises and cooler fluid sinks, creating currents.
Transfer of thermal energy by motion of a fluid (liquid or gas). Heated fluid rises and cooler fluid sinks, creating currents.
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What is conduction in thermal energy transfer, in one accurate sentence?
What is conduction in thermal energy transfer, in one accurate sentence?
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Transfer of thermal energy by direct contact between particles. Particles vibrate and pass energy to neighboring particles.
Transfer of thermal energy by direct contact between particles. Particles vibrate and pass energy to neighboring particles.
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What are the three main mechanisms of thermal energy transfer a device may need to control?
What are the three main mechanisms of thermal energy transfer a device may need to control?
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Conduction, convection, and radiation. These are the fundamental ways thermal energy moves between objects.
Conduction, convection, and radiation. These are the fundamental ways thermal energy moves between objects.
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Which term names a limit like "mass must be less than $1,\text{kg}$"?
Which term names a limit like "mass must be less than $1,\text{kg}$"?
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Constraint. Constraints set boundaries that cannot be exceeded.
Constraint. Constraints set boundaries that cannot be exceeded.
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What is the most common criterion statement format for thermal control using measurable performance?
What is the most common criterion statement format for thermal control using measurable performance?
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Maintain a target temperature range for a set time. Specific, measurable goals allow objective testing of success.
Maintain a target temperature range for a set time. Specific, measurable goals allow objective testing of success.
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What is the meaning of a design constraint when building a device to control thermal energy transfer?
What is the meaning of a design constraint when building a device to control thermal energy transfer?
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A limitation on the design, such as cost, size, or materials. Constraints restrict design choices due to practical limitations.
A limitation on the design, such as cost, size, or materials. Constraints restrict design choices due to practical limitations.
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Which surface property is a key criterion to increase radiative heating: high absorbance or high reflectivity?
Which surface property is a key criterion to increase radiative heating: high absorbance or high reflectivity?
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High absorbance. Dark surfaces absorb more radiation, increasing heat gain.
High absorbance. Dark surfaces absorb more radiation, increasing heat gain.
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Which surface property is a key criterion to reduce radiative heat transfer: high reflectivity or high absorbance?
Which surface property is a key criterion to reduce radiative heat transfer: high reflectivity or high absorbance?
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High reflectivity. Reflective surfaces bounce radiation away, reducing heat absorption.
High reflectivity. Reflective surfaces bounce radiation away, reducing heat absorption.
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What material property is a key criterion for a conductor used to spread heat quickly?
What material property is a key criterion for a conductor used to spread heat quickly?
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High thermal conductivity. Conductors transfer heat efficiently through high conductivity.
High thermal conductivity. Conductors transfer heat efficiently through high conductivity.
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What material property is a key criterion for an insulator used to slow conduction?
What material property is a key criterion for an insulator used to slow conduction?
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Low thermal conductivity. Insulators resist heat flow, requiring low conductivity materials.
Low thermal conductivity. Insulators resist heat flow, requiring low conductivity materials.
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