Grade 9 ADV Physics - PHY41 Practice Flashcards

A Comprehensive set of flashcards covering Power, States of Matter, Kinetic Particle Model, Gas Laws, Thermal Properties, Thermal Energy Transfers, and Reflection of Light based on the PHY41 Grade 9 ADV Physics lecture notes.

Power

The rate of doing work or the rate of energy transfer, defined mathematically as $P = \frac{W}{t}$ or $P = \frac{\Delta E}{t}$.

Watt ($W$)

The SI unit of power, where $1\,W = 1\text{ Joule/second}$.

Efficiency

A measure of performance calculated as $\frac{\text{useful power output}}{\text{total power input}} \times 100\%$.

Boiling Point

The temperature at which a liquid boils throughout and changes state from liquid to gas; for water, this is $100\,^\circ C$.

Melting Point

The temperature at which a solid starts to melt into a liquid; for water, this is $0\,^\circ C$.

Solid

A state of matter where molecules are tightly packed in fixed positions, have a definite volume and shape, and can only vibrate.

Liquid

A state of matter where molecules are close together but not tightly packed, move among each other, and have a definite volume but no definite shape.

Gas

A state of matter where molecules move around freely, exert virtually no force on each other, and fill their container with no definite volume or shape.

Brownian Motion

The random zig-zag motion of microscopic particles in a suspension caused by random collisions with light, fast-moving molecules of a gas or liquid.

Absolute Zero

The lowest possible temperature ($-273\,^\circ C$ or $0\,K$) where particles have the least kinetic energy and all motion stops.

Kelvin Scale

The SI scale for temperature that starts at absolute zero, related to Celsius by the formula $T(\text{in } K) = \theta(\text{in } ^\circ C) + 273$.

Boyle's Law

The relationship stating that the pressure and volume of a fixed mass of gas are inversely proportional at constant temperature, represented as $PV = \text{constant}$ or $P_1V_1 = P_2V_2$.

Gas Pressure

The force per unit area on the walls of a container caused by atoms or molecules hitting the walls and changing momentum.

Specific Heat Capacity ($c$)

The energy required per unit mass per unit temperature increase, calculated using the equation $c = \frac{\Delta E}{m \Delta \theta}$.

Thermal Expansion

The increase in volume of solids, liquids, and gases as their temperature rises and particles vibrate or move more, taking up more space.

Condensation

The change of state from gas to liquid as molecules lose energy, move more slowly, and come closer together.

Solidification

The change of state from liquid to solid as molecules move more slowly and take fixed places; also known as freezing.

Thermal Conduction

The transfer of thermal energy by collisions between particles and, in metals, by the movement of free (delocalized) electrons.

Convection

The method of thermal energy transfer in fluids (liquids and gases) caused by the movement of warmer, less dense fluid rising and cooler fluid falling.

Thermal Radiation

The transfer of energy by infrared radiation (electromagnetic waves) which does not require a medium and can travel through a vacuum.

Normal

An imaginary line drawn perpendicular ($90^\circ$) to a reflective surface at the point where a ray of light strikes it.

Angle of Incidence ($i$)

The angle between the incident ray and the normal.

Angle of Reflection ($r$)

The angle between the reflected ray and the normal.

Law of Reflection

A principle stating that for a ray of light hitting a flat reflective surface, the angle of incidence is equal to the angle of reflection.

Virtual Image

An optical image formed by a plane mirror that is the same size and distance as the object but cannot be projected onto a screen.