Sources of Light
Give one evidence that light is energy.
turns into chemical energy, TE, Electromagnetic
can clearly see through the material
transparent
Unit of luminous flux
lm
Describe the image if the object is located between focal and mirror.
Virtual, larger, upright
cause sunburn and increase risk of skin cancer
ultraviolet light
What source of light produces coherent light?
lasers
A pigment is named by the color of light it _____.
reflects
what is the law of reflection?
angle of incidence = angle of reflection
incident ray, reflected ray, and normal ray lie in the same plane
What is one use of concave mirrors in everyday life?
make-up mirror
used to heat water molecules in food
microwaves
Light-emitting diodes
What are the secondary colors of pigment?
r, g, b
DAILY TRIPLE: the visible light power per unit area landing on a surface is ___________
illuminance
Describe the image if the object is located beyond center.
real, inverted, smaller, between center and focal
electromagnetic radiation produced by accelerating charges in a conductor or conductive medium
radio waves
How do gas-discharging tubes work?
large potential difference produces a current in the tube, and causing valence electrons to move to higher energy levels then return to lower emitting visible light
Why is broccoli green?
absorbs red and blue and reflects green
In a convex mirror, describe the image.
upright, smaller, virtual
DAILY DOUBLE: Describe the image if object is located at center.
real, inverted, same size, located at center
used in medical imaging to diagnose health issues in the body
x-rays
How does cold light work? What is bioluminescence?
produced by chemical rxns involving minimum heat (bioluminescence is production of cold light by living things)
Draw a Venn Diagram of the colors of light?
R G B , Y, M C, W
smooth surface reflects light so that a clear image is visible
specular reflection
Describe the image if the object is located between the focal and center.
real, inverted, larger, located beyond center
decreasing wavelength
increasing energy and frequency