Light and Optics

Question 9:(a) Explain the way to construct a compound microscope using two lenses. In your answer, state the type of lens that you chose, estimate the focal length of the lenses and characteristics of the image formed by each lens.(b) Why is an astronomical telescope not suitable to be used to see distant objects on … Read more

Question 7:A sailor in the navy is looking at the situation on the surface of the sea through a submarine periscope. He found that the Sun is setting. The captain of the submarine told the sailor that the Sun had in fact already set.(a) Is the statement of the captain of the submarine true? Explain … Read more

Question 5:When light from a star travels into the Earth’s atmosphere, its direction of travel will change. This situation is shown in Figure 5. The change of direction is represented by the angle Δθ = i − r.(a) Speed of light in air is 299 910 km s−1 and speed of light in vacuum is … Read more

Question 3:Figure 3 shows a light ray travelling from air to water and then entering a glass block. The refractive index of water is 1.33.(a) Determine angle x.(b) If speed of light in air is 3.0 × 108 m s−1, what is the speed of light in water?(c) Between water and glass, which medium has … Read more

Question 1:Diamond is a precious stone that always appears shiny. Critical angle of diamond in air is 24°.(a) (i) What is the meaning of critical angle? (ii) Determine the value of refractive index of diamond.(b) Figure 1 shows three diamonds of different shapes. A ray enters each diamond as shown in Figure 1. Complete the … Read more

Question 1:Figure 6.47 shows a pupil looking in the direction of a plane mirror and a convex mirror of the same size.(a) Complete the path of light for both types of mirrors.(b) Which type of mirror can produce a wider field of vision? Answer:(a) Mistake on question, path of light is actually moving towards the … Read more

Question 1:A pupil is supplied with an eyepiece lens which has focal length, fe = 7 cm and four pieces of objective lenses A, B, C and D as shown in Table 6.11.1. Complete Table 6.11.2. State two lenses which can produce the largest image.3. State two lenses which can produce the brightest image.4. Based … Read more

Question 1:A concave lens with a focal length of 25 cm forms a virtual image of an ant at a distance of 20 cm from the optical centre of the lens.(a) What is the original position of the ant?(b) Draw a ray diagram to show the formation of a virtual image of the ant.Answer:(a)$$ \begin{aligned} … Read more

Question 1:Figure 6.35 shows an image seen through a convex lens with focal length of 10 cm.1. What are the characteristics of the image?2. Draw a ray diagram to show how the image in the figure is formed.3. Suggest a suitable position to place the object to produce an inverted image. Answer:(a)Characteristics of the image:– upright– … Read more

Question 1:Figure 6.28 shows the path of light which travels from air to a prism.(a) Determine the angle of refraction of light ray in the prism. The refractive index of the prism is 1.50.(b) Will the light ray experience total internal reflection at the side AB of the prism? Explain your answer.Answer:(a)$$ \begin{aligned} &\begin{aligned} n … Read more