Waves Flashcards
What types of energy is there? (7)
Kinetic, Potential, Heat, Light, Sound, Electrical, Radio waves
What are waves?
Waves are vibrations that transfer energy from place to place without matter (solid, liquid or gas) being transferred. The medium may vibrate though.
What’s a medium?
Some waves must travel through a substance. The substance is known as the medium and it can be solid, liquid or gas. Sound waves and seismic waves are like this. They must travel through a medium, and it is the medium that vibrates as the waves travel through.
What kind of waves don’t NEED to travel through a medium, but can if they have to? (4)
Visible light, infrared rays, microwaves and other types of electromagnetic radiation. Electrical and magnetic fields vibrate as the waves travel.
Whats a wavelength?
From 1 crest to another, or from one compression to another.
What is the amplitude?
The distance between the crest or trough, to the equilibrium.
What’s the frequency of a wave?
The frequency of a wave is the number of waves produced by (or pass a point) a source each second.
What can humans see?
Visible light, which is a very small part of the EM spectrum.
What does EM stand for?
Electromagnetic Waves.
How do people see?
People see when light waves from a source reflect off an object and their eyes from all directions.
List the types of waves from smallest to largest energy.
Radio waves (AM, FM, TV, Radar)
Microwaves
Infared
Light
Ultraviolet
X-Rays
Gamma Rays
List the types of waves from smallest to largest wavelengths.
Gamma Rays
X-Rays
Ultraviolet
Light
Infared
Microwaves
Radio waves (Radar, TV, FM, AM)
How are the colours of visible light made?
Electromagnetic energy of various frequencies and wavelength. Red has the largest wavelength and violet, the smallest.
What is white light made up of?
All the wavelengths of visible light. When white light is refracted, it splits into all its component colours
How is a rainbow produced?
A raindrop acts like a prism causing white light to refract, and the colours all bend at different angles.
What colours can only be seen when a certain combination of wavelengths is present?
Pink and Brown
What is the colour of an object determined by?
The wavelengths of light it reflects. So, if an object reflects one wavelength, it absorbs all the other wavelengths of visible light. An objects that absorbs all light is black and an objects that reflects all light is white.
What are the 2 types of lenses?
Convex (curve outwards aka converging) and concave (curve inwards aka disverging).