Physics Unit Study Guide: EM Waves

Flashcards covering key concepts related to electromagnetic waves and light physics.

Electromagnetic Wave

A type of wave that can travel through empty space and matter.

Electromagnetic Spectrum

The complete range of all electromagnetic waves.

Infrared

A type of EM wave that humans detect as heat.

Rays

Straight lines along which light travels.

Speed of Light in Vacuum

300,000 km/s.

Refraction

The bending of light when it passes from one medium to another.

Clear Reflection

Occurs when light strikes a smooth surface producing a sharp image.

Diffuse Reflection

Occurs when rough and dull surfaces cause light rays to reflect at different angles.

Translucent Material

A material that transmits some light that strikes it but scatters it.

Opaque Material

A material that reflects or absorbs all the light that strikes it.

Primary Colors of Light

Red, Blue, Green.

Primary Colors of Pigments

Cyan, Magenta, and Yellow.

Real Image

Images formed by the actual meeting of light rays, always upside down.

Virtual Image

Images formed when light appears to meet up, always right side up.

Convex Mirror/Lens

A surface that is curved outward like the back of a spoon.

Concave Mirror/Lens

Surfaces that curve inward, like a cave.

Rods and Cones

Cells of the eye responsible for color detection, detail, and daytime vision.

Light

Energy that can travel as a wave or as a beam of photons (particles).

EM Spectrum Order

Radio, Microwave, Infrared, Visible, Ultraviolet, X-ray, Gamma.

Colors of Visible Light

Red, Orange, Yellow, Green, Blue, Indigo, Violet (ROYGBIV).

Longest Wavelength EM Wave

Radio waves.

Most Energy EM Wave

Gamma rays.

Skin Cancer Cause

Ultraviolet radiation.

Heat Sensation EM Wave

Infrared waves.

Cell Phone Signal EM Wave

Radio/Microwave waves.

Refractive Index

Ratio of speed of light in a vacuum to the speed of light in a given medium.

Reflected Wavelengths

Wavelengths we see when viewing colors.

White Light Composition

Made of all colors (ROYGBIV).

Filtered Light Observation

Only colors available in the filter can be seen; all others absorbed.

Law of Reflection

Angle of incidence equals angle of reflection.

Image Definition

A copy of an object formed by reflected or refracted light.

Concave Mirror Images

Both real or virtual images based on the location of the object to the focal point.

Convex Mirror Image

Always forms a virtual image.

Concave Lens Image

Always forms a virtual image.

Convex Lens Image

Can form a real or virtual image based on position to the focal point.

Focal Point

The point where light rays meet.

Prism Function

Refracts light and separates it into individual wavelengths.

Mirage Definition

An image of a distant object caused by refraction of light.

Uses of Light

Optical instruments, Lasers, Fiber Optics.

Optical Instruments Definition

Devices/Tools that use light and lens or mirrors.

Lasers Definition

Light that has the same wavelength of color (Coherent Light).

Optical Fibers Definition

Long thin strands of glass or plastic that carry light long distances without losing it.

Transparent Material

A material that transmits most, if not all, of the light that strikes it.