3.2.2. Refraction of light
A subsection of Physics, 0625, through 3. Waves
Listing 10 of 128 questions
A student draws a diagram to represent the electromagnetic spectrum. is the student’s diagram. visible light gamma-rays X-rays ultrasound radiation infra-red radiation microwaves earthquake waves increasing wavelength The student has made two mistakes. On , cross out what is wrong and correct the diagram. The speed of light in an optical fibre is 2.0 × 108 m / s. State the speed of light in a vacuum. speed of light = For light in the material from which the optical fibre is made, calculate 1. the refractive index, refractive index = 2. the critical angle. critical angle = shows a section of the optical fibre. ray optical fibre Light is travelling in the optical fibre. State the full name of the process that takes place each time the light changes direction.
0625_w16_qp_42
THEORY
2016
Paper 4, Variant 2
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A ray of light in glass meets a boundary with air. In , the three diagrams X, Y and Z each show a different angle of incidence for the ray. glass air ray X glass air Y glass air Z Write down the letter of any diagram, X, Y or Z, in which the ray undergoes 1. refraction, 2. total internal reflection. On , use the letter C to mark the critical angle for light at the glass-air boundary. Water waves move more slowly in shallow water than in deep water. shows wavefronts of a wave in deep water meeting the boundary with some shallow water. wave moves in this direction wavefronts deep water shallow water Using your ruler, carefully complete the wavefronts 1, 2 and 3, showing their possible positions in the shallow water where they move more slowly. Tick the one box that describes what is happening at the boundary. diffraction echo refraction total internal reflection
0625_m15_qp_22
THEORY
2015
Paper 2, Variant 2
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shows parallel wavefronts of a light wave in ice. The wavefronts are incident on a boundary with air. direction of wave air ice The speed of the light wave in air is 3.0 × 108 m / s. The refractive index of the ice is 1.3. On : draw the wavefronts of the wave that passes into the air draw arrows to show the direction of travel of the refracted wave label the angle of incidence i and the angle of refraction r. Calculate the speed of the light wave in the ice. speed =
0625_m19_qp_42
THEORY
2019
Paper 4, Variant 2
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A ray of light passes through a length of curved optical fibre. Draw a diagram showing the fibre and the path of the ray of light. Describe one use of optical fibres in medicine. You may draw a diagram. 1 10 Draw a straight line from each wave on the left to the most appropriate speed. light in air 90 m / s (9 × 10) 6000 m / s (6 × 103) 100 000 m / s (1 × 105) 1 000 000 m / s (1 × 106) 300 000 000 m / s (3 × 108) 60 000 000 000 m / s (6 × 1010) microwaves in a vacuum sound in steel The refractive index of a block of glass is 1.5. Use your value for the speed of light from to calculate the speed of light in this block. speed = [ 1 10
0625_s16_qp_41
THEORY
2016
Paper 4, Variant 1
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Visible light is one component of the electromagnetic spectrum. In the table, place a tick in the box next to the approximate value of the speed of light in air. speed m / s 3.0 × 1010 3.0 × 108 3.0 × 106 3.0 × 104 3.0 × 102 The frequency of a light wave is 4.8 × 1014 Hz. Calculate the wavelength of this light in air. wavelength = Light is travelling in an optical fibre that is made of glass. The glass has a refractive index of 1.5. 1. Explain why the quantity refractive index does not have a unit. 2. Calculate the speed of light in the glass. speed = Describe one use of optical fibres in communication technology.
0625_w17_qp_43
THEORY
2017
Paper 4, Variant 3
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Questions Discovered
128