Physical Science Test 2 Vocab

Thermometer

Is an instrument that utilizes the physical properties of materials for the puropose of accurately determining temperature

Thermal Expansion

Is the physical property most commonly used to measure temperature

Kinetic

Is the energy that produces motion of molecules

Potential

Is the energy that causes stretching and compressing of molecular bonds

Internal Energy

The total kinetic and potential energies

Heat

Is the energy that is transferred from one object to another as a result of a temperature difference

Claorie

Is the amount of heat necessary to raise 1 g of pure water by 1°C at normal atmospheric pressure

Kilocalorie

Is the amount of heat necessary to raise 1 kg of pure water by 1°C at normal atmospheric pressure

Specific Heat

Is the amount of heat necessary to raise the temperature of 1 kg of substance 1°C

Freezing

Liquid to Solid

Condensation

Gas to Liquid

Melting

Solid to Liquid

Vaporization

Liquid to Gas

Sublimation

Solid to Gas

Deposition

Gas to Solid

Conduction

Is the transfer of heat by molecular collision

Thermal Conductivity

Is the measure of a substance ability to conduct heat

Convection

Is the transfer of heat by the movement of substances

Radiation

Is the process of transferring energy by means of EM (electromagnetic) waves

Wave

When matter is disturbed energy and manatees from the disturbance, the propagation of energy from this disturbance is known as

Longitudinal waves

Particle motion in the wave velocity are parallel to each each other

Transversal waves

Particle motion is perpendicular to the direction of the wave velocity

Wavelength

Is the distance of one complete wave

Amplitude

Is the maximum displacement of any part of the wave from the equilibrium position

Frequency

Is the number of oscillations that occur during a time

Period

Is the time it takes for a wave to travel a distance of one wavelength

Electromagnetic waves

Consist of vibrating electric, and magnetic field, that oscillate perpendicular to each other in the direction of wave propagation

Sound

Is the propagation of longitudinal waves through matter

Infrasonic

f < 20 hz

Audible

20 Hz < f < 20 kHz

Ultrasonic

f > 20 kHz

Intensity

Is quantitive and is a measure of the rate of energy transfer through a given area

The Doppler Effect

Is the apparent change in frequency, resulting from the relative motion of the source and the observer

Optics

Is a branch of physical science associated with common applications involving light and vision

Geometrical (ray) optics

Use lines or light rays to explain reflection and refraction and used to explain mirrors and lenses

Physical (wave) optics

Takes into account wave effects and use to explain, polarization interference and diffraction

Reflection

Is the change in direction of a wave when it strikes and rebounds from a surface or the boundary between two media

Ray

Is a straight line that represents the path of light

Beam of Light

Is a group of parallel rays

Refraction

Is bending of light waves caused by a speed change as light goes from one medium to another

Spectrometer

Is a device that will separate out the characteristic spectra that are emitted by the heated substance

Concave/Converging Mirror

Is the inside surface of a spherical section

Convex/Diverging Mirror

Is the outside of a spherical section

Convex/Converging Lens

Are thicker at the center than the edges

Concave/Diverging Lens

Are thicker at the edges and thinner at the center

Rods

Are more sensitive and are responsible for light and dark vision

Cones

Are responsible for color vision

Nearsightedness

Is the ability to see nearby objects, clearly, but not distant objects

Farsightedness

Is the ability to see distant objects clearly, but not nearby objects

Polarization

Is the preferential orientation of the field vectors

Electrical Force

Is the ability at the microscopic level to hold atoms and molecules together

Law of Charges

States that like charges repel and unlike charges attract

Colulomb’s Law

States that the force between two charged bodies is directly proportional to the product of the two charges and inversely proportional to the square of their distance apart

Current

Is the time rate of flow of electrical charge

Electrical Conductors

Are materials in which in electrical charge flows readily for example metal

Electrical Insulators

Are materials that do not conduct electricity very well, for example rubber

Semi-Conductor

Are materials that are not good as a conductor or an insulator for an example graphite

Voltage

Is the amount of work it would take to move a charge between two points divided by the value of the charge

Open Switch

Not a complete circuit and no flow of current (electrons)

Closed Switch

A complete circuit and flow of current (electrons)

Direct Current (DC)

Occurs when the electron flow is always in one direction from negative to positive

Alternating Current (AC)

Occurs when the voltage is constantly changing from positive to negative and back

Law of Poles

States that like poles repel and unlike poles attract

Magnetic Field

Is a set of imaginary lines that indicates the direction in which a small compass needle would point if it were placed near a magnet