Physics 2 test 1
a negative magnification for a mirror means that
the image is inverted and the mirror is concave
the eye can't focus when an image is closer than
the near point
converging lenses refract toward
the optical axis
minimum resolving power of a microscope is
1/2 the wavelength of light
the wavelength of the visible spectum
400-700
the scales on the butterfly wings are actually made of a transparent material with index of refractions 1.56- why does light reflect from the surface of the scales?
The scales' index of refraction is different from that of air
real images can be made with
a concave mirror or a convex lens
a converging lens creates
a real, inverted image (if the object is past the focal pt)
a virtual image cannot be formed on
a screen
light of____ colors has a maximum at the_____ of the pattern so that central maximum looks white
all; center
what causes the color of the morpho butterflies wings to change
as the angle changes, the differences in paths among light reflected from different surfaces change, resulting in constructive interference for a different color
suppose we replace the lens in the video with one that has a longer focal length to keep the image in focus how should we move the screen
away from the lens
when you look at an object in a mirror the image is
behind the mirror
Joe's eyes are focused on the tree, so the squirrel and the mountain appear out of focus. This is because the image of the squirrel is formed ______ and the image of the mountain is formed _____.
behing the fovea/ between the lens and fovea
when light hits the boundary between two different materials, it can undergo
both reflection and refraction
apertures for the diffraction studied in this chapter are
both single slit and a circle
Rayleigh's criterion for resolution
central max of diffraction pattern lies on the first dark fringe of the other
if the width of a double slit is doubled without changing the distance what happens to the width of each fringe
decrease
spacing of the other maxima____ on the wavelength, so different colors will have bright fringes_____
depends; at different places
variances by half a wave length result in
destructive lower intensity fringes
Any kind of wave spreads out after passing through a small enough gap in a barrier. This phenomenon is known as
diffraction
Joe is nearsighted, and when he puts on his glasses, he can see the mountain clearly. To adjust for his nearsightedness, his glasses must contain _____ lenses.
diverging
the eye is most relaxed when the image is very
far away( and the object is near the focal point)
hyperopia
farsightedness; light rays focus behind the retina
if the magnification of a microscope is increased then the
focal length of the object lens is decreased
____ doesn't change based on mediums, but ____ does
frequency; wavelength
what will hapen to the fring spacing if the wavelength of the light is decreased
fringe separation will decrease
what will happen to the fringe spacing if the distance to the screen is decreased
fringe spacing will decrease
what will happen to the fringe spacing if the spacing between the slits is decreased
fringe spacing will increase
as the number of slits of diffraction grating increases, the bright fringes observed on the viewing screen
get narrower
reflected ray= ________ ray and both are _____ to the surface
incident; perpendicular
With an expanded pupil diameter, what will happen to the total amount of light energy that reaches the retina
increase
if the width of a double slit is doubled without changing the distance what happens to the brightness of each fringe
increase
Joe now shifts his focus from the tree to the squirrel. To do this, the ciliary muscles in his eyes must have _____ the curvature of the lens, resulting in a(n) _______ focal length for the cornea-lens system. Note that curvature is different from radius of curvature.
increased/decreased
a magnifier makes things appear larger because
it allows you to observe an object held very close to your eye, so the image is large on your retina
light appears slower in different mediums because
it gets absorbed and reemitted in each material
if the width of a double slit is doubled without changing the distance what happens to the intensity of the bright fringes
it increases
if the diameter of a lens is reduced, what happens to the magnification produced by the lens
it is unchanged
if the width of a double slit is doubled without changing the distance what happens to the fringe spacing
it stays the same
With an expanded pupil diameter what will happen to the spread of the image on the retina
it will decrease
if you increase the diameter of a telescope
it will have the same magnification because it has the same focal length, but has more light collecting power
with a decreased spread in image size, what will happen to the intesity of the central maxima
it will increase
what can one say about the image produced by a thin lens that produces a positive magnification?
its virtual and erect
Joe first focuses his attention (and his eyes) on the tree. The focal length of the cornea-lens system in his eye must be __________ the distance between the front and back of his eye.
less than
if there is no phase change or 2 then
m= constructive and m+.5= destructive
if only one phase change occurs
m= destructive and m+.5= constructive
the closer you are to an object the
more divergent the light rays
snells law of refraction
n1sinθ1 = n2sinθ2
the magnification is greatest when the image is at the
near-point distnce and the eye has to fully accomodate
myopia
nearsightedness; light rays focus in front of the retina
the focal length of a converging lens is the distance at which
parallel light rays are focused
if the distance between the object and the focal point is reduced?
the image becomes larger
telescope has only two lenses but a
really long focal length
in a rainbow light refraction which color is on top
red-refracted the least bc has the higher frequency
a converging lens brings rays of light together at a focal point- the bending of light rays is the result of
refraction of the light through the lens
a lens produces a sharply focused inverted image on a screen- if half the screen is covered
the image is dimmed
the wave model of light is needed to explain many of the phenomena discussed in this chapter. which of the following can be understood without appealing to the wave model
sharp-edged shadows
ray is transmitted into a material with a higher index
smaller angle with the normal
Sunsets are red because
sunlight must pass through more atmosphere, and this scatters even more light at bluer wavelengths, transmitting mostly red light. and it is a longer distance/focal length
this video describes the optics of two similar systems
the camera and the eye
total internal reflection
the complete reflection that takes place within a substance when the angle of incidence of light striking the surface boundary is less than the critical angle
is the frequency of this (5.3x10^14) light wave higher, lower, or the same upon entering glass
the same
the fundamental resolution of an optical instrument is set by
the wave nature of light
the resolution of a camera or other optical system is determined by the relationship between what two scales
the wavelength and the size of the aperature
acetone is added to the wings of the morpho butterfly and the color changes- what is the property of light in acetone
the wavelength of the light is less than in air
a lens produces a sharply focused inverted image on a screen- if you remove the lens
their is no image
the color of a soap bubble is due to
thin film interference
rank in order of speed the materials - glass, air, water, diamond, vacuum
vacuum>air>water>glass>diamond