Grade 11 General Science Midterm Reviewer - Physics of Electricity, Light, and Sound

Comprehensive vocabulary flashcards generated from Grade 11 General Science Midterm notes covering Physics of Electricity, Physics of Light, and Physics of Sound.

Charge Dichotomy

The principle that two positive or negative charges repel each other, while a positive and a negative charge attract each other.

Charge Conservation

The principle stating that the algebraic sum of all electric charges in any closed system is conserved.

Charge Quantization

The expression of a given charge quantity into indivisible natural units, where the fundamental electron charge is $e = 1.602 \times 10^{-19}\,C$.

Conductors

Materials containing freely moving electrons that permit the flow of electric charge.

Insulators

Materials in which electrons are bound to atoms, preventing the flow of electric charge.

Static Electricity

The buildup of electric charge on the surface of objects.

Current Electricity

The continuous flow of electric charge through a circuit.

Renewable Energy

Energy naturally replenished and sustainable with lower environmental impact, such as biomass, hydropower, geothermal, wind, and solar.

Nonrenewable Energy

Energy relying on finite sources that take millions of years to form and contribute to pollution and climate change, such as coal, oil, and natural gas.

Philippine Energy Mix

The proportion of power generation in the Philippines consisting of about $75\%$ fossil fuels (coal, natural gas, oil) and about $25\%$ renewable sources.

Transmission Lines

High-voltage lines supported by tall metal towers designed to transport electricity over long distances while minimizing energy loss.

Distribution Lines

Lines that deliver electricity into neighborhoods and buildings after step-down transformers reduce its voltage to a safer level.

Energy Consumption Formula

The mathematical equation used to calculate electrical energy used over time: $\text{Energy (kWh)} = \text{Power (kW)} \times \text{Time (h)}$.

Electric Current ($I$)

The flow of electric charge through a conductor, measured in Amperes ($A$) where $1\,A = 1\,\text{coulomb/second}$ and calculated as $I = \frac{Q}{t}$.

Direct Current (DC)

Electric current in which charges flow continuously in only one direction.

Alternating Current (AC)

Electric current in which charges oscillate back and forth.

Voltage ($V$)

The electric potential difference or energy per unit charge pushing electrons through a conductor, measured in Volts ($V$) where $V = \frac{W}{Q}$.

Resistance ($R$)

The opposition to the flow of current in a conductor, measured in Ohms ($\Omega$).

Electric Power ($P$)

The rate at which electrical energy is transformed into other forms of energy, measured in Watts ($W$).

Light Wave

A transverse electromagnetic wave consisting of electric and magnetic fields oscillating perpendicularly to each other and to the direction of propagation.

Photons

Small packets of energy composing light that describe its particle behavior in phenomena such as the photoelectric effect.

Speed of Light

The speed at which light travels in a vacuum, equal to approximately $3.00 \times 10^8\,m/s$.

Crest

The highest point of a wave representing maximum positive displacement from the equilibrium position.

Trough

The lowest point of a wave representing maximum negative displacement from the equilibrium position.

Amplitude

The height of a wave from its rest position to a crest or trough, indicating the energy carried by the wave.

Wavelength ($\lambda$)

The distance between two consecutive identical points on a wave, such as crest to crest or compression to compression, measured in meters ($m$).

Frequency ($f$)

The number of complete wave cycles passing a fixed point per second, measured in Hertz ($Hz$).

Period ($T$)

The total time required to complete one full wave cycle, calculated as $T = \frac{1}{f}$ and measured in seconds ($s$).

Reflection

The bouncing of light or sound waves off a surface.

Refraction

The bending of a wave as it travels from one medium to another due to a change in speed.

Dispersion

The process of separating white light into its component colors when passing through a medium such as a prism.

Diffraction

The bending or spreading of waves around obstacles or through narrow openings.

Constructive Interference

The wave combination occurring when crests align with crests and troughs align with troughs, producing brighter light or louder sound.

Destructive Interference

The wave combination occurring when a crest aligns with a trough, resulting in darker light or cancelled sound.

Rods

Photoreceptor cells in the retina that detect dim light, enable night vision, and perceive shades of black, white, and gray.

Cones

Photoreceptor cells in the retina that function best in bright light to detect color and produce sharp, detailed vision.

Accommodation

The process by which the eye alters the shape of its lens via ciliary muscles to keep images focused on the retina at varying distances.

Myopia

Nearsightedness, a vision condition where light focuses in front of the retina, corrected using a concave lens.

Hyperopia

Farsightedness, a vision condition where light focuses behind the retina, corrected using a convex lens.

Astigmatism

A vision condition caused by uneven curvature of the cornea, corrected using a cylindrical lens.

Convex Lens

A converging lens that is thicker at the center and brings light rays together to a focal point.

Concave Lens

A diverging lens that is thinner at the center and spreads light rays apart.

Convex Mirror

A mirror curved outward that diverges reflected light rays, always forming a virtual, upright, and reduced image.

Concave Mirror

A mirror curved inward that converges reflected light rays to a focal point.

Laser

Light Amplification by Stimulated Emission of Radiation, producing a highly focused, coherent, and monochromatic light beam.

Total Internal Reflection

The complete reflection of light inside a medium, such as a fiber optic cable, when hitting a boundary at or above a critical angle.

Sound Wave

A longitudinal mechanical wave produced when particles in a medium vibrate parallel to the direction of wave travel.

Compression

A region in a sound wave where particles of the medium are pushed close together under high pressure.

Rarefaction

A region in a sound wave where particles of the medium are spread apart under low pressure.

Speed of Sound in Air Formula

The equation determining sound speed in air relative to temperature: $v = 331\,m/s + (0.6\,m/s/^{\circ}C) \times \text{Temperature}$.

Echo

A repeated sound produced when sound waves bounce off a distant surface.

Reverberation

A series of overlapping echoes caused by sound reflecting rapidly off nearby surfaces in an enclosed space.

Doppler Effect

The observed change in frequency or pitch of a sound wave due to relative motion between the source and listener.

SONAR

Sound Navigation and Ranging; underwater technology emitting sound pulses to measure distance based on returning echo time.

SOFAR Channel

Sound Fixing and Ranging channel; a horizontal layer in the ocean around $1000\,m$ deep where sound travels long distances with minimal energy loss.

Ultrasound

High-frequency sound waves reflected off internal organs to produce diagnostic real-time images known as sonograms.

Kingfisher-Inspired Nose Design

An aerodynamic nose shape implemented on high-speed bullet trains to smoothly enter tunnels and eliminate tunnel booms caused by air compression.