Science 8 Unit 2 Pack: Name Page 0
Section 4.1 : The Properties of Waves Pages By the end of section 4.1 you should be able to understand the following: Waves are disturbances that transmit energy from one place to another Waves have amplitude, wavelength, and frequency Words to Know Definition amplitude crest energy frequency trough wave wavelength Draw and label the main features of a wave Page 1
1. Name and describe the two major types of waves. Use pictures, too! 2. Section 4.2: Properties of Visible Light Pages By the end of section 4.2 you should be able to understand the following: Different colours of light have different wavelengths White light is a mixture of many wavelengths of light A prism can separate and recombine different colours of light light Words to Know Definition reflection refraction spectrum visible light wave model of light Page 2
1. List in order the colours of a prism (the rainbow). 1. 2. How are colours produced by refraction? 2. 3. Describe what Newton discovered about white light and the different colours of the spectrum. 3. 4. List the primary colours. 4. 5. Describe the role of reflection in producing the colours we see. 5. 6. List the primary pigments. 6. 7. What is the difference between how pigments work compared to coloured lights? 7. Page 3
Section 4.3: Light and the Electromagnetic Spectrum By the end of section 4.3 you should be able to understand the following: Pages The electromagnetic spectrum is made up of waves that are similar to light waves that have much longer or shorter wavelengths. Radio waves, microwaves, and infrared waves have longer wavelengths than visible light. Ultraviolet waves, X rays, and gamma rays have shorter wavelengths than visible light. Words to Know Definition and Example electromagnetic radiation gamma rays infrared waves microwaves radio waves ultraviolet waves X rays Which electromagnetic waves are longer than visible light? Which waves are shorter than visible light? Page 4
a) The longer a wavelength, the its level of energy. a) b) The shorter a wavelength, the its level of energy. b) Section 5.1: The Ray Model of Light Pages By the end of section 5.1 you should be able to understand the following: Ray diagrams help explain how beams of light travel in straight lines and how various materials can be opaque, translucent, or transparent. Mirrors reflect light according to the law of reflection, which states that the angle of incidence equals the angle of reflection. Light rays bend when they pass between two materials of different density. Words to Know Definition angle of incidence angle of reflection angle of refraction normal opaque transparent translucent Example: Example: Example: Page 5
Describe why shadows form. Include a diagram. Describe how light reflects from smooth and rough surfaces. Include a diagram for each. Describe the law of reflection. State what refraction is. What two things happen to a light ray when it hits a transparent medium that is a) denser than the medium it s already in? a) b) b) less dense than the medium it s already in? Include an angle drawing for each! Page 6
Section 5.2: Using Mirrors to Form Images Pages By the end of section 5.2 you should be able to understand the following: Simple mirrors can be plane (flat), convex (curving out), or concave (curving in). The image formed by a concave mirror depends on the distance of the object from the mirror. Convex mirrors form images that are upright and smaller than the object. Words to Know Plane mirror Definition Concave mirror Converging rays Convex mirror Diverging rays focal point 1. Describe the image formed in a plane mirror. Be sure to include both the size and orientation of the image. a) less than 1 focal point away: 2. Describe the 3 types of images formed in a concave mirror when the object is: b) between 1 and 2 focal points away: c) more than 2 focal points away: 3. What are the characteristics of an image formed by a convex mirror?
Section 5.3: Using Lenses to Form Images Pages By the end of section 5.3 you should be able to understand the following: Concave lenses are thinner in the middle than at the edge and diverge light rays. Convex lenses are thicker in the middle than at the edge, and converge light rays. Words to Know lens convex lens concave lens focal length Definition 1. Describe how a) light rays behave when they pass through a concave lens. 1. a) b) concave lenses produce images. b) 2. Describe how a) light rays behave when they pass through a convex lens, and 2. a) b) how convex lenses produce images. b)
Section 6.1: Human Vision Pages By the end of section 6.1 you should be able to understand the following: Light is detected by the eye using the cornea-lens-retina system. Rod cells detect dim light but are not sensitive to colour. Cone cells dominate in bright light and distinguish between colours. Vision deficiencies include near-sightedness, far-sightedness, astigmatism, and deficiencies in distinguishing between different colours. Words to Know Definition/Structure and Function astigmatism blind spot cornea iris optic nerve pupil retina sclera
Create a flow chart to list the parts of the eye that light travels from the cornea to the brain. Describe how an image is formed on the retina, and what a blind spot is. What is the role in vision of rod and cone cells?
Draw and label the parts of the eye. Use the Words to Know as your word list. Describe how light rays behave in normal eyes, nearsightedness, farsightedness, and astigmatism. 1. 3. 2. 4. List and describe the different types of blindness. 1. 2. 3. 4.
Section 6.2: Extending Human Vision Pages By the end of section 6.2 you should be able to understand the following: Eyes, cameras, microscopes, and telescopes have some similarities in the way they operate. Lasers and optical fibres are used to transmit data using light. Words to Know Definition laser light optical fibres refracting telescope refracting telescope total internal reflection 1. Describe how light travels through a light microscope. 2. 3.
1. Describe the different types of telescopes. 2. 3. 4. Compare the parts of a camera to the parts of the human eye. 1. 3. 2. 4. Describe how laser light works and how it is used in surgical and information transmission technology. 1. 2. 3.