Дидактические материалы для работы с учебным пособием С.В. Андриановой «English Thesaurus of Student-Physicist». Учебно-методическое пособие
.pdfUnit 23
MIRRORS AND LENSES
Exercise 1. Follow the link and watch the video:
https://www.youtube.com/watch?v=SddBPTcmqOk
Exercise 2. Answer the questions:
1.What does a basic camera have to capture an image? (a basic camera has a lens that light passes through, and a lens opening behind that, which controls how much light enters the camera)
2.What is the lens in your eye controlled by? (By muscles that charge the focal length in order to focus on objects at varying distances.)
3.How does the retina act in your eye? (It acts as the sensor that captures the image, sending it to the brain in the form of electrical signals.)
4.How can the farsighted see distant objects? (They can see just fine, but when objects are too close, their eyes can’t make light rays converge at the retina, and instead the image forms beyond the retina.)
5.What kind of lenses can correct that? (This can be corrected by eyeglasses with converging lenses that bring light rays closer together to form a clear image on the back of the retina.)
6.How can nearsightedness be corrected? (By diverging lenses, spreading out the light rays so a focused image is formed at the proper distance.)
7.What does a magnifier consist of? (Any simple magnifier consists of a single converging lens, which produces a virtual image that enlarges an object.)
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8.What can be used to show how a magnifier produces a virtual image? (You can use a trusty ray diagram to show how this image forms.)
9.How can you measure a lens’ magnifying power? (By comparing the angles at which light rays enter your eyes. In order to find the magnifying power of the lens, you just divide the angle subtended by the virtual image by the angle subtended by your unaided eye.)
10.What do compound microscopes use to magnify objects? (Compound microscopes which like a telescope, use objective lenses and eyepieces to magnify objects.)
Exercise 3. Give examples of using reflections in myths, fairy tales or everyday life. /Gorgon/
Exercise 4. Are the following statements true (T) or false (F)?
Imperfect images are the result of defects in shape and form. (T)
The images seen in flat mirrors are always virtual for real objects. (T)
Lenses are rarely used to form images by refraction in optical instruments. (F) /commonly used/
A thin lens has one focal point. (F) /two/
A flat mirror produces an image having an apparent leftright reversal. (T)
Exercise 5. Give your comments on the following statement, speak about advantages/disadvantages; your attitude; history of the invention; the way and prospects of using:
Contact lenses make people’s lives better. If the function of augmented reality will be added to them it would be fantastic.
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Unit 24
WAVE OPTICS
Exercise 1. Follow the link and watch the video:
https://www.youtube.com/watch?v=-ob7foUzXaY
Exercise 2. Answer the questions:
1.What is called a diffraction grating? (Light shines through many equally spaced slits.)
2.What is a spectrometer? (A tool that uses diffraction grating or a prism to separate the wavelengths and to learn about the source of the light.)
3.Why can we get information about the light source of solid materials or high pressure gaseous objects? (Because when heated they emit a continuous spectrum of light that covers a very wide range of wavelengths.)
4.What are absorption lines? (They are characteristic wavelengths of light that have been absorbed by the same elements that emitted them.)
5.How can we explain the bright rainbow colors on a soapy bubble surface? (That coloring is also due to interference and the separation of wavelengths, an effect known as thin film interference.)
6.How can we measure the thickness of thin films? (Thin films are layers of material whose thickness can be measured in micrometers, or even nanometers.)
7.What does the kind of interference depend on? (The kind of interference depends on the thickness of the oil (film) and the light’s angle of incidence.)
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8.What wave can we call destructive? (When a wave is out of phase by 180 degrees, it’s destructive.)
9.When can we see no phase shift? (If light reflects off a surface that has a lower index of refraction than the medium it’s passing through, there is no phase shift, and the wave then constructively interferes with itself.)
10.What is called polarization? (The filtering of light depending on its oscillation-direction.)
Exercise 3. Give examples of optical interference we can come across in everyday life. /Rainbow in an oil stain/
Exercise 4. Are the following statements true (T) or false (F)?
Different colors undergo a constructive interference at different angles. (T)
Constructive interference creates a visible, colored reflection. (T)
When a wave is in phase with another wave, their crests and troughs /trof/ are amplified. (T)
Light is a transverse wave. (T)
When a wave strikes an object, the effects of the changing electric field are felt in a direction that’s parallel to the direction, in which the wave is moving. (F) /perpendicular/
Exercise 5. Give your comments on the following statement, speak about advantages/disadvantages; your attitude; history of the invention; the way and prospects of using: Not all sunglasses can be useful for us. Why? How is polarization used in them?
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Unit 25
OPTICAL INSTRUMENTS
Exercise 1. Follow the link and watch the video:
https://www.youtube.com/watch?v=SddBPTcmqOk&t=243s
Exercise 2. Answer the questions:
1.What does a camera have to capture an image? (To capture an image, a basic camera has a lens that light passes through.)
2.What person can we call farsighted? (Someone who’s farsighted can see distant objects just fine.)
3.What kind of lenses can be used to correct nearsightedness? (Nearsightedness can be corrected by diverging lenses, spreading out the light rays so a focused image is formed at the proper distance.)
4.What does a simple magnifier consist of? (Any simple magnifier consists of a single converging lens, which produces a virtual image that enlarges an object.)
5.How does the iris control the amount of light which enters your eyes? (The iris controls how much light enters your eye, opening up while it’s dark and contracting in the presence of bright light.)
6.How can we measure a lens’ magnifying power? (You can measure a lens’ magnifying power by comparing the angles at which light rays enter your eyes.)
7.What does a refracting telescope consist of? (It consisted of an objective lens on the end closest to the object and an
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eyepiece at the other end, which magnified the image produced by the objective lens.)
8. How are the objects viewed through the refracting telescope? (Any objects viewed through the refracting telescope would be upside down.)
9. What is necessary to study objects on the cellular scale? (e.g. compound microscopes)
10. Which equation is applicable for all of optical
instruments? (magnification equation M= /to find
the magnification power we divide the height or distance of image into the height or distance of object/. We can use the equations in terms of distance and height for both objects and images.)
Exercise 3. Read the formula: M= /m equals h sub i over
h sub o/
Exercise 4. Are the following statements true (T) or false (F)?
An eye focuses light and produces an image. (T)
Lenses can be measured in diopters. (T)
Combining lenses are use in a compound microscope. (T)
There are three fundamentally different types of telescope.
(F) /two: the refracting and the reflecting telescopes/
A microscope can be used to see an atom. (F) /In order to be seen, the object must be at least as large as a wavelength. An atom is many times smaller./
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Exercise 5. Give your comments on the following statement, speak about advantages/disadvantages; your attitude; history of the invention; the way and prospects of using etc.:
We should not spend money on inventing new telescopes, we have got enough. We’d better use spacecraft instead.
Unit 26
RELATIVITY
Exercise 1. Follow the link and watch the video:
https://www.youtube.com/watch?v=AInCqm5nCzw
Exercise 2. Answer the questions:
1.What does the theory of special relativity explain? (It explains the behavior of things that move very fast.)
2.Why was it necessary? (Regular Newtonian physics doesn’t always apply in such cases.)
3.Why is it called special relativity? (Because it only applies to specific situations: where the different frames of reference aren’t accelerating.)
4.How do we call such frames of reference? (They’re called inertial reference frames.)
5.What is special relativity built around? (Two main assumptions, or postulates. The first says that the laws of physics are the same in all inertial reference frames. The second postulate says that the speed of light in a vacuum is
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the same for all observers – about 300,000,000 meters per second.)
6.What is called time dilation? (When time changes (and speed is always constant) that’s called time dilation).
7.What’s called length contraction? (When distance changes (and speed is always constant) that’s called length contraction.)
8.When does time dilation occur? (Time dilation occurs when another reference frame is moving relative to you, so time in that reference frame slows down relative to the time you measure.)
9.What factor is called “gamma”? (We call this factor gamma, and it applies to any situation where another inertial reference frame is moving relative to yours.)
10.Is there universal concept of simultaneity? Why not? (Because time can pass differently for people depending on their frame of reference, there’s also no universal concept of simultaneity.)
Exercise 3. Give examples of the most common use of the relativity theory in everyday life. (GPS and GLONASS systems of navigation.)
Exercise 4. Are the following statements true (T) or false (F)?
The speed of light is always constant. (T)
The speed of the electron always remains less than the speed of light. (T)
Galilean relativity in mechanics also applies to experiments in electricity and other areas. (F)
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In relativistic mechanics, there is no such thing as absolute length or absolute time. (T)
Time scales are altered by gravity (according to the theory of relativity). (T)
Exercise 5. Give your comments on the following statement, speak about advantages/disadvantages; your attitude; history of the invention; the way and prospects of using; being ecological-friendly etc.:
Real-time fusion will become practical one day due to the theory of relativity.
Unit 27
QUANTUM PHYSICS
Exercise 1. Follow the link and watch the video:
Part 1: https://www.youtube.com/watch?v=7kb1VT0J3DE – revision.
Part 2: https://www.youtube.com/watch?v=qO_W70VegbQ – more about the unit content.
Exercise 2. Answer the questions:
Part 1: https://www.youtube.com/watch?v=7kb1VT0J3DE
1.How can light behave? (Light could be have as a wave and also behave like a particle.)
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2.What is a blackbody? (No true blackbodies exist, but in theory, they absorb all incoming light without reflecting any, and radiate energy accordingly.)
3.How can you predict the intensity of the energy coming from a blackbody? (You can predict the intensity of the energy coming from a blackbody – or blackbody radiation
– based on its temperature.)
4.What problem did physicists come up with an equation for the intensity of the energy coming from a blackbody, using the idea that light is a wave (The Rayleigh-Jeans law (the equation) predicted that if you summed up the contributions of higher and higher frequencies to calculate the total power emitted by a blackbody, you’d find infinite power. Which contradicts the principle of conservation of energy.)
5.What concept was the Planck’s law based on? (The concept it was based on was that electromagnetic energy takes the form of tiny, discrete packets, called quanta. In other words, at a certain point, you can’t divide energy into anything smaller than these packets.)
6.What did Einstein win a Nobel prize for it in 1921? (Einstein argued that light energy traveled in packets we now call photons, which would essentially make light behave like a particle.)
7.How did Einstein prove that light travelled in these discrete packets? (He suggested an experiment involving the photoelectric effect.)
Part 2: https://www.youtube.com/watch?v=qO_W70VegbQ
1. Сan light be both a particle and a wave? (Yes.)
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