Topic 1,2 & 3-Light & Optics Flashcards
What are the four properties of light?
Light travels in straight lines
Light can be reflected
Light can bend
Light is a form of energy
What is an optical device?
Any technology that uses light
What are translucent materials?
Allows some light to pass through but not all
What are transparent materials?
Light travels straight through the material
What are opaque materials?
Do not allow any light to pass through them
What is regular reflection?
Occurs when light rays hit a smooth surface. The incoming rays travel parallel to each other. When these rays strike a smooth surface they all bounce off in the same direction and the rays are reflected at the same angle
What is diffuse reflection?
Occurs when light rays hit a rough or uneven surface. When the light rays hit the surface they reflect but due to the rough surface each of the rays is reflected at a different angle. The rays to not remain parallel
What are incident rays?
The incoming rays
What are plane mirrors?
Flat mirrors that provide the clearest reflections
What is the law of reflection?
When a ray of light hits a plane mirror at an angle, it bounces off the mirror surface at exactly the same angle
What is a normal in the law of reflection?
A line perpendicular to the mirror at the point of reflection
What is the angle of incidence in the law of reflection?
The angle between the incident ray and the normal
What is the angle of reflection in the law of reflection?
The angle between the reflected ray and the normal
What is a concave mirror?
Reflecting surface that is curved inward
What is a focal point?
Concave mirrors reflect parallel ray of light back through the focal point
What happens to an image in a concave mirror if the object is farther away from the focal point?
The image is upside down and small
What happens to an image in a concave mirror if the object is in between the focal point and the mirror?
The image appears upright and enlarged
What is a convex mirror?
Reflecting surface that curves outward
What happens to the parallel rays of light that reflect off a concave mirror?
They gather inwards toward the focal point
What happens to the parallel rays of light that reflect off a convex mirror?
They reflect outwards away from the focal point
What is refraction?
When light travels from one substance to another it bends or refracts
What is a concave lens?
Piece of transparent material that is thinner in the middle than at the edges
What happens to parallel rays of light that pass through a concave lens?
The rays of light diverge and spread out
What is a convex lens?
A piece of transparent material that is thicker in the middle than the edges
What happens to parallel rays of light when they pass through a convex lens?
It brings the light rays together much like a concave mirror
What is the wave model of light?
Models used to explain the characteristics and behaviour of light energy. It describes light as energy in the form of waves. The different colours of light have different wavelengths
What is amplitude?
Height of the wave from its middle test position to its highest point
What is the crest?
Highest point of a wave
What is the wavelength?
The distance from the crest of one wave to the next
What is the frequency?
The number of times the medium vibrates in a given amount of time
What colour has the highest wavelength but the lowest frequency?
Red
What colour has the lowest wavelength but the highest frequency?
Violet
What is electromagnetic radiation?
All forms of radiant energy (visible light, infrared ration, ultraviolet radiation, radio waves, X rays, etc.)
What is the electromagnetic spectrum?
Refers to the whole range of wavelengths of visible and invisible electromagnetic radiation
