Science 30 Unit C: Electromagnetic Energy

Science 30 Unit C: Electromagnetic Energy

Chapter 2 Assignment Summary Science 30 Unit C: Electromagnetic Energy Chapter 2 Assignment Total Possible Marks 57 For Teacher s Use Only Your Mark Teacher s Comments This document is intended for You may find the following Internet sites useful: Students Teachers Administrators Home Instructors General Public Other Alberta Education, http://www.education.gov.ab.ca Learning Resources Centre, http://www.lrc.education.gov.ab.ca Tools4Teachers, http://www.tools4teachers.ca Exploring the electronic information superhighway can be educational and entertaining. However, be aware that these computer networks are not censored. Students may unintentionally or purposely find articles on the Internet that may be offensive or inappropriate. As well, the sources of information are not always cited and the content may not be accurate. Therefore, students may wish to confirm facts with a second source. Copyright 2007, Alberta Education. This resource is owned by the Crown in Right of Alberta, as represented by the Minister of Education, Alberta Education, 055 02 Street, Edmonton, Alberta, Canada T5J 4L5. All rights reserved. This resource was developed by or for Alberta Education. It may be reproduced in any form, including photocopying, without written permission from Alberta Education provided that associated copyright notices are also reproduced. THIS RESOURCE IS NOT SUBJECT TO THE TERMS OF A LICENCE FROM A COLLECTIVE OR LICENSING BODY, SUCH AS ACCESS COPYRIGHT.

57 Chapter 2 assignment This Assignment Booklet is worth 57 marks out of the total 52 marks for the assignments in Unit C. The value of each assignment and each question is stated in the left margin. Read all parts of your assignment carefully, and record your answers in the appropriate places. If you have difficulty with an assignment, go back to the textbook and review the appropriate lesson. Be sure to proofread your answers carefully before submitting your Assignment Booklet. Chapter 2 Assignment: The Electromagnetic Spectrum For questions to 0, read each question carefully. Decide which of the choices BEST completes the statement or answers the question.. Which grouping lists the individual bands of the electromagnetic spectrum from high frequency to low frequency? A. X-rays, gamma rays, radio waves, infrared B. gamma rays, infrared, radio waves, X-rays C. gamma rays, X-rays, infrared, radio waves D. infrared, radio waves, gamma rays, X-rays 2. Which grouping lists the individual bands of the electromagnetic spectrum according to increasing wavelength? A. radio waves, ultraviolet light, visible light, X-rays B. radio waves, visible light, ultraviolet light, X-rays C. X-rays, ultraviolet light, visible light, radio waves D. visible light, ultraviolet light, radio waves, X-rays 3. Vancouver shortwave radio transmitter CKZU of the Canadian Broadcasting Corporation broadcasts at a frequency of 660 khz. What is the wavelength of the radio signal coming from this transmitter? A. 24.4 km B. 24.4 m C. 48.7 km D. 48.7 m

2 4. The following diagram shows several wavelengths of a beam of electromagnetic radiation. 240 m The wavelength of this electromagnetic radiation is A. 20 m B. 60 m C. 40 m D. 30 m 5. In 969, Apollo astronauts placed a special reflector on the Moon. This reflector sends light back in the direction from which it came, regardless of its angle of incidence. With the Moon about 384 000 km from Earth, how long would it take a light pulse sent from Earth to reach the lunar reflector and then return to Earth? A..28 s B. 2.56 s C. 3.85 s D. 5.3 s 6. The chloroplasts within the leaves of green plants contain the pigment chlorophyl. This pigment provides energy for photosynthesis by absorbing the energy contained in the photons of A. green light B. red light C. violet light D. red light and violet light 7. What kind of electromagnetic radiation is responsible for sunburns? A. UVA light B. UVB light C. visible light D. infrared light v

3 8. High-energy electrons collide against a metal surface to produce what kind of electromagnetic radiation? A. visible light B. gamma rays C. shortwaves D. X-rays 9. What form of electromagnetic radiation can most effectively penetrate human tissue? A. visible light B. microwaves C. UV light D. X-rays 0. Which form of electromagnetic radiation is most destructive to chemical bonds in living tissue? A. gamma rays B. UV rays C. visible light D. X-rays. Decide whether each statement is true (T) or false (F). Place your answer in the blank space given. a. Cosmic rays are part of the electromagnetic spectrum. b. Electromagnetic radiation is a beam of tiny particles with some mass moving at a high speed through space. c. Orange light is a type of electromagnetic radiation. d. UVC is a form of ionizing radiation. e. Visible light is a form of ionizing radiation. f. Infrared light has a greater wavelength than does red light.

2 2. Match each description with the appropriate term listed. Place your answer in the blank space given. i. centimetre ii. frequency iii. hertz iv. wavelength a. a unit for frequency b. a unit for wavelength c. the distance required for one complete cycle d. the number of cycles per second 3. A student was wondering why electromagnetic radiation can travel through the vacuum of outer space. The student had learned that sound cannot travel through this region. Explain why electromagnetic radiation can travel in outer space. 4. In the investigation Electromagnetic Radiation Transfers Energy, the intensity of EMR in a spectrum of light was measured by a photovoltaic cell. a. Indicate which membrane of the eye serves a function similar to the photovoltaic cell used in the investigation. Explain your answer. b. The photovoltaic cell was not only moved within the visible spectrum but also in the dark region just beyond the visible spectrum s red end. The photovoltaic cell produced a current even in this dark region. Explain why a current could be produced by the photovoltaic cell while it was in the dark region next to the red light.

3 5 5. A cellphone emits a radio signal with a frequency of 90 MHz. Determine its wavelength. 6. A student noticed that sunglasses rated for both UVA and UVB protection were not rated for UVC protection. However, the student learned that UVC radiation is far more damaging to body tissues than either UVA or UVB radiation. Explain why UVC protection for anyone going outside even on a sunny day is much less important than UVA and UVB protection. Return to page 8 of the Distributed Learning Student Guide, and begin Lesson 2.2. For questions 7 to 27, read each question carefully. Decide which of the choices BEST completes the statement or answers the question. 7. Which part of the Sun emits UV light? A. middle atmosphere B. lower atmosphere C. solar flares D. surface 8. The Sun s solar flares mostly emit A. radio waves, X-rays, and gamma rays B. radio waves, visible light, and X-rays C. infrared light, visible light, and X-rays D. radio waves and visible light

9. Which type(s) of electromagnetic radiation emitted by the Sun are absorbed by Earth s atmosphere and do not reach Earth s surface? A. long-wave radio waves, X-rays, and gamma rays B. short-wave radio waves and gamma rays C. infrared light, X-rays, and gamma rays D. X-rays 20. A student is wearing a pair of sunglasses designed to reduce the glare from reflected surfaces. When the student tilts her head to the side and back again, she notices that the brightness of the blue sky changes in intensity. The student wonders why the intensity is affected by the orientation of her sunglasses. The light coming from the sky toward her sunglasses has most likely undergone A. absorption B. diffraction C. polarization D. refraction 2. During an investigation, a student aimed a beam of light through a round opening in an opaque barrier. The light passing through the opening travelled to a screen a short distance away. When the student repeated the procedure with the beam going through a smaller opening, he found that the circular projection of light on the screen became larger with less distinct edges. What is responsible for the change in characteristics of the circular projection? A. diffraction of light B. reflection of light C. refraction of light D. polarization of light

7 22. A beam of visible light is aimed at the air-glass boundary, as shown in the following diagram. air glass I II III Which path will the refracted light beam most likely take after it hits the boundary? A. I B. II C. III D. IV 23. A beam of visible light is aimed at the air-glass boundary, as shown in the following diagram. III air glass II I Which path will the reflected light beam most likely take after it hits the boundary? A. I B. II C. III D. IV

24. According to current theories of star evolution, the final stage of the Earth s Sun is predicted to be a A. nebula B. black hole C. neutron star D. white dwarf 25. Which telescope is designed with mirrors along the inside of its body tube? A. Chandra s X-ray telescope B. Galileo s telescope C. Kepler s telescope D. Newton s telescope 26. Refer to the handout Reference Absorption Spectra. Which gases produced this spectrum? A. hydrogen and boron B. hydrogen and helium C. magnesium and boron D. sodium and helium 27. Refer to the handout Reference Absorption Spectra. Which gases produced this spectrum? A. iron B. boron C. sulfur D. titanium

28. Match each description with the appropriate term listed. Place your answer in the blank space given. i. diffraction ii. polarization iii. reflection iv. refraction a. the return of a wave from a surface b. the bending of light that occurs when its speed changes c. the bending of a wave as it passes by the edges of an opening d. the process in which the vibration of a wave is confined to one direction 29. Match each description with the appropriate term listed. Place your answer in the blank space given. i. bright-line spectrum ii. continuous spectrum iii. dark-line spectrum iv. Doppler-shifted spectrum a. a spectrum associated with light passing through an energy-absorbing medium b. a spectrum of light emitted from an excited gas under low pressure c. a spectrum of light from a moving celestial object d. a spectrum having no lines or bands 30. Match each description with the appropriate term listed. Place your answer in the blank space given i. black hole ii. pulsar iii. supernova iv. white dwarf a. a region in which the gravitational field is so strong that neither matter nor electromagnetic radiation can escape from it b. a compact star in the last stage of a low-mass star c. a stellar explosion that produces a bright cloud of ionized gas d. a rotating neutron star

2 3 3 0 3. Inuit people traditionally call the Great Bear constellation Tukturjuit, or stars representing a caribou. Describe two ways in which the stars of Tukturjuit were important to the Inuit traditional lifestyle. 32. The nuclear fusion at the Sun s core releases gamma-ray photons. Explain why the photons that emerge from the Sun s surface are visible-light photons and infrared-light photons rather than gamma-ray photons. 33. Explain why the receiving dish of a radio telescope must be larger than an optical telescope in order for radio telescopes to have adequate resolution.

3 2 34. The nuclear fusion at the Sun s core releases gamma-ray photons. Explain why these photons emerge from the Sun s surface as visible light and infrared-light photons. 35. Refer to the following diagrams. While observing a star, an astronomer finds that its spectrum includes the lines for strontium. When she examines the spectral lines for strontium in the starlight, she finds that the lines are slightly misaligned with strontium s known spectrum. Explain this difference between the known and observed spectral lines for strontium in the starlight. 36. When using X-ray technology in a medical diagnosis, there are both risks and benefits to the patient. 2 a. Describe one risk.

b. Describe one benefit. 2 c. A physician makes a decision not to take an X-ray image of a seemingly minor injury to a patient s knee. Assume the physician considered the risks and benefits of taking the X-ray image before making her decision. Which set of factors dominated the decision mode by the physician the risks or the benefits? Explain your answer. Submit your completed to your teacher for assessment. Then return to page 22 of the Distributed Learning Student Guide, and begin the Chapter 2 Summary.