is10_sb_unit_d

Connect Your Understanding
18. Use the wave model of light to explain the
difference between infrared light and
ultraviolet radiation. t
19. Explain why it is not possible to increase both
the frequency and the wavelength of a wave
at the same time. t
20. Black light (shown below) refers to any light
source that produces primarily ultraviolet
radiation.
(a) Provide a possible reason why it is called
black light. a
(b) Describe a use for black light. a
Question 20
21. (a) Write a sentence that describes the
relationship between the energy of
electromagnetic radiation and its
frequency. c
(b) Write a sentence that describes the
relationship between the energy of
electromagnetic radiation and its
wavelength. c
22. What is a possible disadvantage of using
fluorescent bulbs? t
23. Provide two reasons why an LED would be a
preferable light source to an incandescent or
fluorescent light bulb. a
24. Describe the conditions necessary to create a
penumbra. t
25. Draw a flowchart that shows the steps of how
a plasma screen creates a display of colours.
c
26. Give two reasons why a plasma display might
be preferable to an LCD display. a
27. If white light produced from the primary
colours red, green, and blue reflects off a
yellow surface and then passes through a
prism, what colours will be present? a
28. Explain why a colour inkjet printer can still
print black characters even when its black ink
cartridge has run out. a
29. Describe why a photographer or film
producer would want the lighting director to
use two or more lights in most of the scenes
being photographed. a
Reflection
30. What can you explain about light and its
properties that you were not able to explain
before reading this chapter? c
After Reading
Reflect and Evaluate
How do graphics help you to understand text? Write
a one-paragraph explanation for struggling readers to
summarize how graphics can help them to
understand new ideas and information. Exchange
paragraphs with a partner, and revise your
suggestions based on new ideas from your partner’s
paragraph.
Unit Task Link
Look at streetlights in your neighborhood to see what
kind of light pollution they create. Think about ways
that this light pollution could be reduced by using a
shade over the light. Will the material you use be
transparent, translucent, or opaque? Research
streetlights that reduce light pollution. Start your
research at ScienceSource.
Light is part of the electromagnetic spectrum and travels in waves.
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