Electromagnetic Waves

 

Topic #	Old Topic	Old # Hrs	New Topic #	New Topic	New # Hrs
			G	Electromagnetic waves	15/22
			G1	Nature of EM waves and light sources	4
			G.1.5	Distinguish between transmission, absorption and scattering of radiation.
			G.1.6	Discuss examples of the transmission, absorption and scattering of EM radiation. Students should study the effect of the Earth?s atmosphere on incident EM radiation. This will lead to simple explanations for the blue colour of the sky, red sunsets or sunrises, the effect of the ozone layers, and the effect of increased CO2 in the atmosphere. This links with 8.5.6.
			G.1.9	Outline the mechanism for theproduction of laser light. Students should be familiar with the term population inversion.
			G.1.10	Outline an application of the use of a laser. Students should appreciate that lasers have many different applications. These may include: medical applications, communications, technology (bar-code scanners, laser disks) industry (surveying, welding and machining metals, drilling tiny holes in metals), production of CDs, reading and writing CDs, DVDs, etc.
			G2	Optical instruments	6
			G.2.2	Define the power of a convex lens and the dioptre.
			G.2.3	Define linear magnification.
			G.2.5	Distinguish between a real image and a virtual image.
			G.2.6	Apply the convention "real is positive, virtual is negative" to the thin lens formula.
			G.2.7	Solve problems for a single convex lens using the thin lens formula.
10.3	Moved from additional Higher Level		G3	Two-source interference of waves	3
H.6	Moved from Options SL & HL		G4	Diffraction grating	2
				Electromagnetic waves HL only
			G5	X-rays	4
			G.5.4	Solve problems involving accelerating potential difference and minimum wavelength.
			G.5.5	Explain how X-ray diffraction arises from the scattering of X-rays in a crystal. This may be illustrated using 3 cm equipment.
			G.5.6	Derive the Bragg scattering equation.
			G.5.7	Outline how cubic crystals may be used to measure the wavelength of X-rays. Students should be aware of the fact that the structure of DNA was discovered by means of X-ray diffraction.
			G.5.8	Outline how X-rays may be used to determine the structure of crystals.
			G.5.9	Solve problems involving the Bragg equation.
			G6	Thin-film interference	3
			G.6.2	Explain how wedge fringes can be used to measure very small separations. Applications include measurement of the thickness of the tear film on the eye and oil slicks.
			G.6.3	Describe how thin-film interference is used to test optical flats.
			G.6.4	Solve problems involving wedge films.
			G.6.9	Describe the difference between fringes formed by a parallel film and a wedge film.
			G.6.10	Describe applications of parallel thin films. Applications should include: design of non-reflecting radar coatings for military aircraft, measurement of thickness of oil slicks caused by spillage, design of non-reflecting surfaces for lenses (blooming), solar panels and solar cells.