chemistry and physics unit test 5 lessons 9, 10, 11

Sound: a vibration

Sound wave: a moving vibration

Echo: a sound you hear a second time

Mach 1: 760 miles per hour

Supersonic speed: anything faster than 760 mph.

Sonic boom: the sound of something breaking the sound barrier.

Infra-sound: a sound too low for us to hear.

Pitch: how we describe the sound we hear.

Timbre: quality of sound.

Sonar: sound navigation and ranging.

Bio-acoustics: study of sound made by wildlife.

Nuclear fusion: when particles join together and fuse

Radiant energy: light

Incandescent light: light hot enough to glow.

Light emitting diode: LED

Opaque: if light can’t pass through something.

translucent/transparent: if light can pass through.

Shadow: Blocked light.

Electromagnetic energy:Energy that reaches from the sun to the earth.

Invisible spectrum: colours we can’t see

Colour spectrum/ visible spectrum: everything we can see

Ultraviolet: higher frequency than violet

Infrared: has longer wavelengths and generates heat

Angle of incidence: the angle of reflection

Refraction: bending of light

Laws of thermodynamics: four special laws that deal with energy and all kinds of matter

Thermodynamics: the study of thermal energy.

Zeroth law: if two bodies are each in thermal equilibrium with some third body, then they are also in equilibrium with each other

First law of thermodynamics: energy and matter can never be created or destroyed.

second law of thermodynamics: the universe as a whole is becoming less and less organised.

Entropy: a measure of disorder.

Third law of thermodynamics: the entropy of a system reaches its minimum the cooler it gets.

Heat source: the hotter of two items.

Heat sink: the cooler of two items

Radiation: energy that moves through space

Radiant heat: heat that moves through space

Convection: heat that transfers from liquids

Sea breeze: air over the ocean that rushes in to fill the space rising air leaves.

Land breeze: the air that replaces a sea  breeze

Conduction: when a heat source and heat sink are connected through matter

Combustion: chemical reaction when something reacts with oxygen

Fire triangle: heat, fuel, oxygen.

Fahrenheit: US way to measure heat. 32 degrees fahrenheit to one degree celsius.

Celsius: was to measure heat outside of the US. The boiling point of water is 100 degrees and the freezing point of water is 0 degrees celsius.

Kelvin: form of measurement for heat that scientists use. Water freezes at 273.15 kelvins and boils at 373.15 Kelvins.

Thermal expansion: when things expand as they heat up.