science light

light

electromagnetic radiation that you can see

radient energy

what kind of energy does light carry?

phones/communication

example of radio waves

microwave/spacecraft communication

example of microwaves

heat sensitive pictures

example of infrared waves

photosynthesis

example of visible light

black light/sun/tanning beds

example of ultra-violet waves

bones

example of x-rays

earth's atmosphere

example of gamma rays

frequencies and wavelengths

what determines the difference between the electromagnetic spectrum?

1 - amplitude 2 - persons perception of light 3 - distance from light source 4 - eye sensitivity to light

what are three things that change how bright/intense a light is?

vacuum

what medium does light travel through fastest?

solid

What medium does light travel through slowest?

in a vacuum, the molecules are further apart and solids are closer together so light travels faster in a vacuum because there are fewer molecules that the light has to pass through

why does light travel through a vacuum faster that a solid?

light transmits through glass

what is an example of evidence that light transmits through materials?

light is absorbed by solar panels and black fabric

what is an example of evidence that light absorbs into materials?

light reflects off mirrors and white clothing

what is an example of evidence that light reflects off materials?

transparent - a material that allows almost all the light striking it to pass through and through which the objects can be seen clearly translucent - a material that allows most of the light striking it to pass through but through which the objects appear blurry

what are two types of material that light can transmit through? explain their meaning?

light-blocking curtains/wood/counters/floor

what are some materials that are opaque?

light bounces off you, strikes the mirror, and bounces back to your eye

how are you able to see your reflection in a mirror?

law of reflection

when a wave is reflected from a surface, the angle of reflection is equal to the angle of incidence

virtual image

an image that forms from light rays that diverge

concave mirror

a mirror that curves inward

convex mirror

a mirror that curves outward

convex - outward

concave - inward

what's the difference between concave and convex?

real image

an image that forms where rays converge

regular reflection

reflection off a smooth hard surface

diffuse reflection

reflection off a rough surface

scattering

when light waves traveling in one direction are made to travel in many directions

refraction

the change in direction of a wave as it changes speed while moving from one medium to another

lower index - faster travel of light

higher index - slower travel of light

how does the speed of a wave change as the index of refraction increases?

If light enters any substance with a higher refractive index (such as from air into glass) it slows down. The light bends towards the normal line. If light travels enters into a substance with a lower refractive index (such as from water into air) it speeds up. The light bends away from the normal line.

how does a light ray direction and speed change as it passes through air-glass-air

concave - diverge

convex - converge

how do convex and concave lenses change how an object is seen?