24 October 2020 Colour LO Explain how colour

24 October 2020 Colour LO: Explain how colour is related to absorption, reflection, and transmission. Do Now (5 min): 1. Define refraction. 2. Describe what happens to the velocity of a wave when it moves from a less dense to a more dense medium. 3. Give the rule for the reflected ray from a plane mirror. 4. Define precision. 5. Describe how to convert from MHz to Hz Challenge: Draw a diagram to show refraction of water waves when they move from deep water to shallow water. Key terms: colour, spectrum, wavelength, filter, absorption, reflection, transmission

24 October 2020 Colour LO: Explain how colour is related to absorption, reflection, and transmission. Do Now Answers: 1. The change in speed and direction of a wave when it changes from one medium to another. 2. It slows down and bends towards the normal 3. Angle of incidence = angle of reflection 4. A set of results that are close to the mean. 5. Multiply by 1, 000 Challenge: Key terms: colour, spectrum, wavelength, filter, absorption, reflection, transmission

24 October 2020 Colour LO: Explain how colour is related to absorption, reflection, and transmission. 40% 50% 60% • Link the colour of light to its wavelength. • Explain why objects appear certain colours. • Describe and explain the effect of filters on light. Key terms: colour, spectrum, wavelength, filter, absorption, reflection, transmission

The electromagnetic spectrum:

specular reflection

diffuse reflection

absorption

transmission transparent translucent

transmission

24 October 2020 Colour LO: Explain how colour is related to absorption, reflection, and transmission. Describe white light. White light is compose of seven different colours. Describe what happens when light is incident on an opaque object. Some wavelengths (colours) are reflected and some wavelengths (colours) are absorbed. State what is observed when An object appears white. all wavelengths of visible light are reflected equally. State what is observed when An object appears black. all wavelengths of visible light are absorbed. What is the colour of an opaque object determined by? Which wavelengths (colours) are more strongly reflected Describe how colour filters Absorbing certain wavelengths (colours) Key terms: colour, spectrum, and wavelength, filter, absorption, work. transmitting other wavelengths reflection, transmission (colours)

24 October 2020 Colour LO: Explain how colour is related to absorption, reflection, and transmission. Describe white light. White light is compose of seven different colours. Describe what happens when light is incident on an opaque object. Some wavelengths (colours) are reflected and some wavelengths (colours) are absorbed. State what is observed when An object appears white. all wavelengths of visible light are reflected equally. Look, cover, write, check State what is observed when An object appears black. all wavelengths of visible light are absorbed. What is the colour of an opaque object determined by? Which wavelengths (colours) are more strongly reflected Describe how colour filters Absorbing certain wavelengths (colours) Key terms: colour, spectrum, and wavelength, filter, absorption, work. transmitting other wavelengths reflection, transmission (colours)

24 October 2020 Colour LO: Explain how colour is related to absorption, reflection, and transmission. Describe white light. White light is compose of seven different colours. Describe what happens when light is incident on an opaque object. Some wavelengths (colours) are reflected and some wavelengths (colours) are absorbed. State what is observed when An object appears white. all wavelengths of visible light are reflected equally. 2 minutes quizzing! State what is observed when An object appears black. all wavelengths of visible light are absorbed. What is the colour of an opaque object determined by? Which wavelengths (colours) are more strongly reflected Describe how colour filters Absorbing certain wavelengths (colours) Key terms: colour, spectrum, and wavelength, filter, absorption, work. transmitting other wavelengths reflection, transmission (colours)

24 October 2020 Colour LO: Explain how colour is related to absorption, reflection, and transmission. Recall Quiz: (5 mins) 1. Which term is used to refer to regular reflection from a smooth surface in a single direction? A. Diffuse reflection B. Specular reflection C. Scattering 2. What name is given to a material that absorbs some wavelengths of visible light and transmits others? A. Filter B. Opaque C. Transparent D. Lens Key terms: colour, spectrum, wavelength, filter, absorption, reflection, transmission

24 October 2020 Colour LO: Explain how colour is related to absorption, reflection, and transmission. Recall Quiz: (5 mins) 3. What is a translucent material? A. A material that can be fully seen through B. A material that cannot be seen through C. A material that transmits light, but no clear shapes can be seen 4. Why can we see through glass? A. Almost all light waves are reflected B. Almost all light waves are transmitted C. Almost all light waves are absorbed Key terms: colour, spectrum, wavelength, filter, absorption, reflection, transmission

24 October 2020 Colour LO: Explain how colour is related to absorption, reflection, and transmission. Recall Quiz: (5 mins) 5. Where do the colours of the rainbow come from? The prism makes the light sparkle because it is shiny The prism adds colours to the light The prism reacts with the light and changes its colour Key terms: spectrum, wavelength, The colour, prism splits up the colours that thefilter, light absorption, is made of reflection, transmission

24 October 2020 Colour LO: Explain how colour is related to absorption, reflection, and transmission. Recall Quiz: (5 mins) 1. Which term is used to refer to regular reflection from a smooth surface in a single direction? A. Diffuse reflection B. Specular reflection C. Scattering 2. What name is given to a material that absorbs some wavelengths of visible light and transmits others? A. Filter B. Opaque C. Transparent D. Lens Key terms: colour, spectrum, wavelength, filter, absorption, reflection, transmission

24 October 2020 Colour LO: Explain how colour is related to absorption, reflection, and transmission. Recall Quiz: (5 mins) 3. What is a translucent material? A. A material that can be fully seen through B. A material that cannot be seen through C. A material that transmits light, but no clear shapes can be seen 4. Why can we see through glass? A. Almost all light waves are reflected B. Almost all light waves are transmitted C. Almost all light waves are absorbed Key terms: colour, spectrum, wavelength, filter, absorption, reflection, transmission

24 October 2020 Colour LO: Explain how colour is related to absorption, reflection, and transmission. Recall Quiz: (5 mins) 5. Where do the colours of the rainbow come from? The prism makes the light sparkle because it is shiny The prism adds colours to the light The prism reacts with the light and changes its colour Key terms: spectrum, wavelength, The colour, prism splits up the colours that thefilter, light absorption, is made of reflection, transmission

24 October 2020 Colour LO: Explain how colour is related to absorption, reflection, and transmission. Application Task – We Do A bottle looks blue in blue light and it looks blue in white light. Why does the bottle look blue in both kinds of light? Key terms: colour, spectrum, wavelength, filter, absorption, reflection, transmission

24 October 2020 Colour LO: Explain how colour is related to absorption, reflection, and transmission. Application Task – We Do A bottle looks blue in blue light and it looks blue in white light. Why does the bottle look blue in both kinds of light? In blue light Blue light does not contain any other colour, just blue. When it lights up the bottle, the bottle _____ blue light. We see the light that the bottle _____. In white light White light contains all the colours of the spectrum. When the bottle is in white light it _____ blue light. The bottle _____ red light and green light. It _____ all of the colours in white light except for blue. We the colour, bottle because the light that it _____. Keysee terms: spectrum, ofwavelength, filter, absorption, reflection, transmission

24 October 2020 Colour LO: Explain how colour is related to absorption, reflection, and transmission. Application Task – We Do A bottle looks blue in blue light and it looks blue in white light. Why does the bottle look blue in both kinds of light? In blue light Blue light does not contain any other colour, just blue. When it reflects blue light. We see the lights up the bottle, the bottle _____ reflects light that the bottle _____. In white light White light contains all the colours of the spectrum. When the reflects blue light. The bottle is in white light it _____ absorbs red light and green light. It _____ absorbs all of the _____ colours in white light except for blue. We the colour, bottle because the light that it _____. reflects Keysee terms: spectrum, ofwavelength, filter, absorption, reflection, transmission

24 October 2020 Colour LO: Explain how colour is related to absorption, reflection, and transmission. Application Task – You Do Explain why the observer sees red in the example below. Key terms: colour, spectrum, wavelength, filter, absorption, reflection, transmission

24 October 2020 Colour LO: Explain how colour is related to absorption, reflection, and transmission. Application Task – We Do Answers The red filter absorbs all of the wavelengths of light except red. The only wavelength that is transmitted is red so that is the colour eyes will see. Key terms: colour, spectrum, wavelength, filter, absorption, reflection, transmission

24 October 2020 Colour LO: Explain how colour is related to absorption, reflection, and transmission. Application Task – You Do Explain these two diagrams. Key terms: colour, spectrum, wavelength, filter, absorption, reflection, transmission

24 October 2020 Colour LO: Explain how colour is related to absorption, reflection, and transmission. Application Task – You Do Answers 2. The blue filter absorbs all of the wavelengths of light except blue. The only wavelength that is transmitted is blue so that is the colour eyes will see. 3. The blue filter absorbs all of the wavelengths of light except blue. The only wavelength that is transmitted is blue but the blue light is then absorbed by the red filter. No wavelengths of light are reaching our eye so we see black. Key terms: colour, spectrum, wavelength, filter, absorption, reflection, transmission

24 October 2020 Colour LO: Explain how colour is related to absorption, reflection, and transmission. Exit ticket: True/False 1. The colour black is not a colour, but the absence of reflected or emitted light. 2. Blue objects reflect mostly blue wavelengths of light and absorb other wavelengths. 3. Violet light has the longest wavelengths. 4. A red filter allows all wavelengths of light except red to be transmitted. 5. Plants appear green because chlorophyll absorbs most wavelengths of light, but reflects green wavelengths. Key terms: colour, spectrum, wavelength, filter, absorption, reflection, transmission

24 October 2020 Colour LO: Explain how colour is related to absorption, reflection, and transmission. Exit ticket: True/False 1. The colour black is not a colour, but the absence of reflected or emitted light. True 2. Blue objects reflect mostly blue wavelengths of light and absorb other wavelengths. True 3. Violet light has the longest wavelengths. False 4. A red filter allows all wavelengths of light except red to be transmitted. False 5. Plants appear green because chlorophyll absorbs most wavelengths of light, but reflects green wavelengths. True Key terms: colour, spectrum, wavelength, filter, absorption, reflection, transmission