PSPhysics Unit 5 - Thermal Energy, Heat Transfer, and Plate Boundaries

Vocabulary flashcards covering states of matter, thermal expansion and contraction, specific heat, methods of heat transfer (conduction, convection, radiation), conductors vs. insulators, tectonic plate boundaries, and calorimetry calculations from the Physical Science Unit 5 study guide.

Solid

The state of matter characterized by particles that are packed tightly together (close), vibrating in place at relatively low speeds, and having the least kinetic energy compared to liquids and gases.

Liquid

The state of matter where particles are close together but able to slide past one another with intermediate speed and an intermediate amount of kinetic energy.

Gas

The state of matter in which particles are spaced far apart, moving at high speeds in random directions, and possessing the most kinetic energy.

Calorimeter

A well-insulated device used experimentally to measure the amount of heat transferred to or from a substance during physical or chemical processes.

Direction of Heat Flow

The fundamental thermal principle stating that thermal energy (heat) naturally and spontaneously transfers from a warmer object to a cooler object.

Thermal Expansion

The increase in the volume of a substance that occurs when its temperature increases because its particles gain kinetic energy and spread farther apart.

Thermal Contraction

The decrease in the volume of a substance that occurs when its temperature decreases because its particles lose kinetic energy and move closer together.

Thermal Energy

The total kinetic and potential energy of all particles within a sample of matter, which depends on both the mass of the substance and its temperature (for example, $400\,\text{g}$ of water at $50\,^\circ\text{C}$ contains more thermal energy than $200\,\text{g}$ of water at $50\,^\circ\text{C}$).

High Specific Heat

A characteristic of substances (such as water) that require a large amount of energy to change temperature, causing them to heat up and cool down slowly.

Low Specific Heat

A characteristic of substances (such as metals like copper and aluminum) that require little energy to change temperature, making them easy to heat up and cool down quickly.

Conduction

Heat transfer between substances that occurs through direct physical contact (buzz word: direct contact), such as burning a hand on a hot metal spoon or feet feeling cold against a bathroom tile floor.

Convection

Heat transfer within fluids (liquids and gases) driven by density differences, where warmer, less dense fluid rises and cooler, denser fluid sinks (buzz word: rising/sinking motion), such as in boiling water or a lava lamp.

Radiation

Heat transfer through electromagnetic waves without requiring matter or physical contact (buzz word: electromagnetic waves), such as sunlight warming a sidewalk or sitting in front of an infrared heating lamp.

Thermal Conductor

A material that transfers heat easily and rapidly, primarily consisting of metals like copper and aluminum.

Thermal Insulator

A material that does not transfer heat easily, used to prevent heat loss or gain (such as wood, air, or styrofoam).

Convergent Plate Boundary

A tectonic plate boundary where plates move toward each other, leading to geological features and events such as mountains, deep-sea trenches, volcanoes, subduction zones, and earthquakes.

Divergent Plate Boundary

A tectonic plate boundary where plates pull apart or move away from each other, resulting in features such as mid-ocean ridges and continental rift valleys.

Transform Plate Boundary

A tectonic plate boundary where plates slide past one another horizontally, typically forming fault lines and causing earthquakes.

$$Q = mc\Delta T$$

The heat transfer formula used in calorimetry calculations, where $Q$ represents heat energy gained or lost, $m$ is mass, $c$ is the specific heat capacity, and $\Delta T$ is the change in temperature ($T_{\text{final}} - T_{\text{initial}}$).

Calorimetry Heat Exchange Principle

The principle of thermal equilibrium and conservation of energy stating that inside a closed calorimeter, the heat lost by the warmer substance equals the heat gained by the cooler substance ($Q_{\text{lost}} = Q_{\text{gained}}$).