# Physics CH 26-28 – Flashcards

## Unlock all answers in this set

question
Video Tutor: Partially Covering a Lens Part A Suppose we replace the lens in the video with one that has a longer focal length. To keep the image sharp, how should we move the screen?
Away from the lens
question
Interactive Figure: Color Addition and Shadows Part A Start with all three light sources on and no object to cast a shadow. If we turn off the blue source, what will the color be in the region that was originally illuminated by all three sources? Part B With all three lights are on, we insert an object that casts a shadow. What will be the colors of the shadows, and why? Part C What are the colors of the shadows cast by an object that is placed under blue and red lights only? What are the colors of the shadows cast by an object that is placed under blue and red lights only?
A- Yellow B- The three shadows will be cyan, yellow, and, because these are the complements of the three primary colors. C- The red light casts a blue shadow and the blue light casts a red shadow, because the space not illuminated by red is illuminated by blue, and vice versa.
question
Video: Model of Refraction Part A When a car veers off the road such that the left front wheel goes off the pavement into the gravel before the right wheel, what will happen to the car, and why? Part B What is the relationship between the direction of traveling rays of light and the line representing the wave crests? Part C What happens to the speed of light waves when they enter water from air? Part D What happens to the wavelength and frequency of the light waves as they enter water from air?
A- The car will tend to turn to the left. Because the left wheel hits the gravel first and slows down before the right wheel, the right wheel covers a greater distance, causing the car to turn to the left. B- The direction of the rays of light is perpendicular to the line representing the wave crests. C- The speed decreases. D- Wavelength decreases, and frequency will stay the same.
question
Eclipses Tutorial Part A Why are lunar eclipses observed more frequently than solar eclipses Part B Why doesn't a total lunar eclipse occur every month? Part C During an annular solar eclipse, ___________. Part D While an observer on Earth sees a total solar eclipse, an astronaut is on the near side of the Moon. What would the astronaut see? Part E Suppose that the Moon were three times smaller than it really is but that its distance from Earth remained the same. Which type of eclipse would NEVER occur? Part F If the Moon's orbit were NOT tilted with respect to the ecliptic, how often would solar eclipses occur? Part G If a person were standing in the Moon's penumbra during a solar eclipse, what would the person see? Part H If you are watching a lunar eclipse in which the Moon is in Earth's penumbra, what will you see?
A- The Moon's shadow covers only a small portion of Earth. B- Sometimes the Moon is above or below Earth's shadow during a full Moon. C- The Moon is too far away from Earth to block the entire Sun. D- Earth's day side, with a dark spot moving across it E- total solar eclipses F- once a month G- the Sun, with a portion of it blocked by the Moon H- the entire Moon, but dimmer than normal
question
Video: The Rainbow Part A When white light strikes a prism, what happens and why? Part B Why does a rainbow look like a curve when viewed from the ground? Part C What would the rainbow look like to a viewer in the sky, and why? Part D What kind of glasses would you wear while watching 3D movies, and why?
A- The white light emerges with the colors separated, with the red light bending the least. B- Raindrops act like prisms that reflect the colors of light in particular angles depending on how the individual colors are bent by the prism. Light seen at that angle forms a bow shape C- The rainbow would appear to be a complete circle, because Earth no longer obstructs our view when we are above. D- glasses with one horizontally polarized and one vertically polarized lens, because one projector is horizontally polarized and the other is vertically polarized
question
Interactive Figure: Refraction Part A When the flashlight is in the air and the refracted ray enters the water, how does the angle of refraction compare with the angle of incidence? Part B When the flashlight is in the air and the refracted ray is in the water, what happens to the angle of refraction if you increase the angle of incidence? Part C When the flashlight is in the water and the refracted ray enters the air, how does the angle of refraction compare with the angle of incidence? Part D When the flashlight is in the water and the refracted ray is in the air, what happens to the angle of refraction if you increase the angle of incidence?
A- The angle of refraction is smaller than the angle of incidence, other than when the flashlight is on the normal line. B- The angle of refraction increases. C- The angle of refraction is greater than the angle of incidence. D-The angle of refraction increases.
question
Interactive Figure: Electromagnetic Spectrum Part A How do the wavelength and frequency of infrared light compare to the wavelength and frequency of ultraviolet light? Part B How does frequency change when wavelength is increased? Part C How does the speed of radio waves compare with the speed of gamma rays?
A- The wavelength of infrared is larger than that of ultraviolet, and the frequency is smaller. B- The frequency decreases. C- The speed of radio waves is equal to the speed of gamma rays.
question
Video: Why the Sky Is Blue and the Sunset Is Red Part A What happens when light from the Sun interacts with the molecules of the atmosphere Part B What kinds of molecules scatter high frequencies of light? Part C What kinds of molecules will scatter the low frequencies of light? Part D Why is the sky blue when the Sun is overhead? Part E Why is the sunset red? Why is the sunset red?
A- The molecules scatter the light. B- small molecules C- large molecules D- The molecules in the atmosphere scatter blue light more than any other light, so the sky looks blue E- Only the low-frequency red light penetrates the thick layers of atmosphere when the Sun is low in the sky.
question
Reading Check 28.14 Part A What is the angle between a light ray and its wavefront?
A right angle
question
Reading Check 28.01 Part A How does incident light that falls on an object affect the motion of electrons in the atoms of the object?
Incident light makes the electrons oscillate. The electrons then emit light or absorb the light and convert it to heat.
question
Reading Check 27.28 Part A What part of the visible electromagnetic spectrum is most absorbed by water?
Red
question
Reading Check 28.09 Part A When is the angle at which a ray of light strikes glass not the same as the angle it exits?
When the light strikes the glass in one medium (such as air) and exits the glass in another medium (such as water)
question
Reading Check 28.11 Part A Does the law of reflection hold for curved mirrors? Explain
Yes. It is as if the curved mirror is made of many small plane mirrors at slightly different orientations to each other.
question
Prelecture Reading Question 26.06 Part A The electromagnetic radiation mostly absorbed in ordinary glass is _________.
ultraviolet
question
Prelecture Reading Question 28.08 Part A Total internal reflection occurs when the speed of light in a material is _________.
less than the speed outside the material
question
Reading Check 27.05 Part A What color light is transmitted through a piece of red glass?
Red
question
Think And Discuss 26.88 Part A How does this tell you how many Suns would fit between the tree and the Sun's 150,000,000-kilometer distance from Earth?
A- The angle from each opening in the leaves to the circles cast on Dean is the same angle between the leaves and the Sun. So 100 Suns would fit between the tree and its position from Earth.
question
Reading Check 27.19 Part A Which type of bell interacts more with high-pitched sounds?
Small bells
question
Think And Explain 28.50 Part A In the multiple images of physics teacher Karen Jo Matsler in (Figure 1) , how many mirrors are involved?
three mirrors
question
Reading Check 27.20 Part A Which particles interact more with high-frequency light?
Small particles
question
Prelecture Reading Question 27.03 Part A When white light is incident upon green glass the color that emerges is _________.
Green
question
Reading Check 28.24 Part A Light normally travels in straight lines, but it "bends" in an optical fiber. Explain.
Total internal reflection keeps the light trapped inside the optical fiber.
question
Prelecture Reading Question 27.08 Part A A sunset appears red in color due to _________.
higher frequencies of light scattered away
question
Reading Check 28.02 Part A What do the electrons affected by illumination do when they are made to vibrate with greater energy? What do the electrons affected by illumination do when they are made to vibrate with greater energy?
They reemit more light or collide with neighbors, thereby converting light energy to more internal energy.
question
Reading Check 26.22 Part A Why are infrared waves often called heat waves?
Infrared light vibrates entire atoms and molecules, and this vibration increases the temperature of the absorbing substance.
question
Reading Check 28.28 Part A What kind of lens can be used to produce a real image? A virtual image?
A real image can only be made with a converging lens. A virtual image can be made with either a converging or diverging lens.
question
Think And Explain 27.59 Part A Your friend says that the reason the distant dark mountains appear blue is because you're looking at the sky between you and the mountains. Do you agree or disagree?
I agree
question
Reading Check 27.07 Part A Which warms more quickly in sunlight - a colorless or a colored piece of glass? Why?
A colored piece of glass warms quickest because it absorbs more frequencies of light, thus converting the energy to temperature.
question
Reading Check 26.02 Part A What does a changing electric field induce?
A changing magnetic field
question
Think And Explain 26.50 Part A Which travels faster through a vacuum - an infrared ray or a gamma ray?
Both travel at the same speed c.
question
Reading Check 26.03 Part A What produces an electromagnetic wave?
An oscillating or accelerating electric charge
question
Prelecture Reading Question 27.02 Part A When a red rose is held in white light, the color of its petals appears _________.
Red
question
Reading Check 28.07 Part A Can a surface be considered polished for some waves and not for others? Cite an example.
Yes. The mesh of a radio dish is polished for long wavelength radio waves and yet rough for short wavelength light waves.
question
Prelecture Reading Question 28.06 Part A Dispersion of light from drops making up a rainbow have undergone refraction and internal _________.
reflection
question
Reading Check 26.08 Part A About how much of the measured electromagnetic spectrum does light occupy? About how much of the measured electromagnetic spectrum does light occupy?
Less than 1 millionth of 1%
question
Reading Check 27.29 Part A What color results when red is subtracted from white light?
Cyan
question
Reading Check 26.06 Part A What do electric and magnetic fields contain and transport?
Energy
question
Think And Discuss 28.111 Part A Do these two rays produce the image or merely locate where the image is in relation to the lens.
The two rays just locate image distance from the lens.
question
Reading Check 28.29 Part A Why is vision sharpest when the pupils of the eye are very small?
Light passes only through the center of the lens, where aberrations are minimal
question
Reading Check 28.27 Part A Distinguish between a virtual image and a real image. Mention in each case whether the image made by a single lens is right-side up or inverted
A virtual image, unlike a real image, cannot be displayed on a screen. A virtual image is upright, whereas a real image is inverted.
question
Reading Check 28.19 Part A Does a single raindrop illuminated by sunlight deflect light of a single color or does it disperse a spectrum of colors? Does it do this by reflection, refraction, or both?
It disperses a spectrum of colors, by both reflection and refraction.
question
Reading Check 27.14 Part A What is the resulting color if equal intensities of red light and cyan light are combined?
White
question
Reading Check 28.12 Part A Is a mirage the result of reflection or refraction? Why does it happen?
Refraction. Light curves through warm, low-density air near the ground, where it travels faster.
question
Reading Check 26.18 Part A What is the fate of the energy in infrared light incident on glass?
Infrared light will make atoms vibrate, thus becoming internal energy and a temperature increase.
question
Think And Explain 28.81 Part A Waves don't overlap in the image of a pinhole camera. Does this feature contribute to sharpness or to a blurry image?
Sharpness
question
Think And Explain 28.52 Part A Her eye at point P looks into the mirror. Which of the numbered cards can she see reflected in the mirror? (Figure 1)
2
question
Reading Check 27.09 Part A What is the color of the peak frequency of solar radiation when it is plotted versus wavelength?
Yellow green
question
Reading Check 27.25 Part A What accounts for the whiteness of a cloud?
Water droplets of different sizes scatter a variety of light frequencies, resulting in a white cloud.
question
Reading Check 28.23 Part A At what angle inside glass is light totally internally reflected? At what angle inside a diamond is light totally internally reflected?
43°, 24.5°
question
Think And Solve 28.42 The diameter of the Sun makes an angle of 0.53∘ from Earth. Part A How many minutes does it take the Sun to move 1 solar diameter in an overhead sky? (Remember that it takes 24 hours, or 1440 minutes, for the Sun to move through 360∘.) Part B How does your answer compare with the time it takes the Sun to disappear, once its lower edge meets the horizon at sunset? Part C Does refraction affect your answer?
A- t = 2.1 min B- It is the a little shorter than time it takes the Sun to disappear. C- Yes
question
Reading Check 26.16 Part A What is the fate of the energy in ultraviolet light that is incident upon glass?
Ultraviolet light will be absorbed by the resonant vibration of electrons and turned into internal energy and a temperature increase.
question
Prelecture Reading Question 26.07 Part A Materials that do not transmit visible light are said to be _________.
opaque
question
Prelecture Reading Question 26.09 Part A The part of the eye that enables us to see colors is the _________.
cones in the retina
question
Prelecture Reading Question 28.01 Part A The blackness of the type on a page is due to _________.
absorption
question
Reading Check 27.26 Part A What is the effect on the color of a cloud when it contains an abundance of large droplets?
The cloud becomes dark.
question
Reading Check 26.10 Part A How does the frequency of a radio wave compare to the frequency of the vibrating electrons that produce it?
They are the same.
question
Reading Check 28.05 Part A Relative to the distance of an object in front of a plane mirror, how far behind the mirror is the image?
The image is the same distance behind the plane mirror as the object is in front of it.
question
Prelecture Reading Question 26.01 Part A Electromagnetic waves are composed of _________.
electric and magnetic fields
question
Prelecture Reading Question 26.02 Part A The electromagnetic waves having the highest speed in free space are _________. The electromagnetic waves having the highest speed in free space are _________.
none in particular as gamma, radio, and light have the same speed
question
Prelecture Reading Question 26.03 Part A The smallest portion of the electromagnetic spectrum is _________.
visible light
question
Reading Check 26.26 Part A Distinguish between an umbra and a penumbra.
No light from the source enters the shadow in an umbra, while some, but not all, light from the source enters the penumbra.
question
Reading Check 26.29 Part A When are objects on the periphery of your vision most noticeable?
When they are moving
question
Reading Check 27.01 Part A Which has the higher frequency, red light or blue light?
Blue
question
Prelecture Reading Question 27.01 Part A Which of these colors of light represents the lowest visible frequency?
Red
question
Reading Check 27.02 Part A What occurs when the outer electrons that buzz about the atomic nucleus encounter electromagnetic waves?
They are forced into vibration, absorbing or emitting electromagnetic waves.
question
Reading Check 27.06 Part A How does a pigment affect light?
A pigment selectively absorbs some frequencies of light and transmits others.
question
Reading Check 27.10 Part A To what color of light are our eyes most sensitive?
Yellow-green
question
Prelecture Reading Question 27.04 Part A When red, green, and blue light are combined, the result is _________.
White
question
Reading Check 27.16 Part A When something is painted red, what color is most absorbed?
Cyan
question
Reading Check 27.17 Part A What are the subtractive primary colors?
Magenta, cyan, and yellow
question
Prelecture Reading Question 27.06 Part A The colors of ink used in CMYK printing are cyan, magenta, yellow, and _________.
black
question
Reading Check 27.23 Part A Why does the Sun look reddish at sunrise and sunset but not at noon?
The longer path length of sunlight at sunrise and sunset scatters out more blue light.
question
Reading Check 27.24 Part A Why does the color of sunsets vary from day to day?
Different particles in the air each day scatter and absorb different wavelengths of light, thus giving the sky many different colors.
question
Reading Check 27.30 Part A Why does water appear cyan?
Water absorbs red light. White minus red is cyan.
question
Prelecture Reading Question 27.10 Part A The color of seawater is a result of the subtraction of what color?
Red
question
Reading Check 28.03 Part A What is Fermat's principle of least time?
Light takes the quickest path in going from one place to another.
question
Prelecture Reading Question 28.03 Part A Specular reflection is common in the light reflected from _________.
a mirror
question
Reading Check 28.15 Part A What is the relationship between index of refraction and the speed of light in a material? What is the relationship between index of refraction and the speed of light in a material?
The index of refraction is inversely proportional to the speed of light in a material.
question
Reading Check 28.17 Part A How does refraction change the apparent depth of a swimming pool?
It makes the pool look shallower - only ¾ as deep.
question
Prelecture Reading Question 28.04 Part A A mirage is the result of atmospheric _________.
refraction
question
Prelecture Reading Question 28.05 Part A Which of the following changes when light is refracted?
Speed
question
Reading Check 28.22 Part A What is meant by critical angle? What is meant by critical angle?
The minimum angle of incidence inside a medium where light is totally reflected
question
Prelecture Reading Question 28.07 Part A A secondary rainbow in the sky is the result of a _________.
a double reflection in drops
question
Prelecture Reading Question 28.09 Part A A feature of a pinhole camera is that the image _________.
is inverted
question
Multiple Choice Question 27.3 Part A What characteristic of light mostly relates to color?
frequency
question
Multiple Choice Question 28.8 Part A The inversion of your image in a plane mirror is actually an inversion of
front-back.
question
Multiple Choice Question 28.13 Part A When light reflects from a surface, there is a change in its
none of the above
question
Prelecture Reading Question 28.02 Part A Light travels a path from one location to another in the least _________.
time
question
Multiple Choice Question 26.2 Part A Electromagnetic waves consist of
oscillating electric and magnetic fields.
question
Prelecture Reading Question 26.04 Part A Materials that clearly transmit visible light are said to be _________.
transparent
question
Multiple Choice Question 26.32 Part A When visible light is incident upon clear glass, atoms in the glass
are forced into vibration
question
Multiple Choice Question 26.17 Part A Compared to the velocity of radio waves in vacuum, the velocity of visible light waves in a vacuum is
the same.
question
Reading Check 26.28 Part A How do the rods in the eye differ from the cones?
The rods are rod-shaped and are more sensitive to dim light. The cones are cone-shaped and are color-sensitive.
question
Prelecture Reading Question 28.10 Part A A magnifying glass widens the angle through which _________.
an object is viewed
question
Reading Check 28.21 Part A Why is a secondary rainbow dimmer than a primary bow? How are the colors arranged in the secondary bow?