RI Y6 Remedial Superpositions Assignment

Raffles Institution Year 5-6 Physics Department 1 2025 Year 6 H2 Physics Remedial Chapter 12: Superposition 1 A double star is at a distance of 20 light years from the Earth. A telescope with a diameter of 3.0 m is used to view the star. (A light year is the distance light travels in a vacuum in one year. This is 159.5 10 m× .) What is the approximate minimum separation between the two stars of the double star that can be detected by the telescope? [1] A 85.0 10 m× B 91.0 10 m× C 103.0 10 m× D 113.0 10 m× 2 A dou ble-slit system with individual slit widths of 0.030 mm and a slit separation of 0.18 mm is illuminated with 500 nm light directed perpendicular to the plane of the slits. What is the total number of bright fringes appearing between the two first order minima of the diffraction pattern? [2] 3 (a) Describe the formation of a stationary wave. [1] (b) A stretched string is used to form a stationary wave. Part of this wave, at a particular instant, is shown in Fig. 3.1. Fig. 3.1 The points on the string are at their maximum displacement. (i) State the phase difference between the particles labelled A and B. [2] (ii) State the number of antinodes shown in Fig. 3.1 for this wave. [1] (iii) The period of vibration of this wave is T. On Fig. 3.1, sketch the stationary wave 0.25T after the instant shown in Fig. 5.1. [1] [SRJC/Prelims 2014/P2/5] A B

Raffles Institution Year 5-6 Physics Department 2 4 (a) While Alvin drives through a long underground tunnel in Singapore, it is obvious that nothing can be seen a few metres into the tunnel without additional sources of light . However, his radio continues playing songs from Gold 90.5FM, which is broadcast at a frequency of 90.5 MHz, and his Global Positioning System (GPS) continues to display his car position. Further into the tunnel, the GPS reports that it has lost its connection with the satellites but his radio continues to play. (i) State the type of e lectromagnetic waves that Alvin ’s GPS system uses to communicate with its satellites. Explain how you come to this conclusion. [2] One particular day, the traffic was particularly heavy in the tunnel. When driving very slowly, Alvin finds that there were many points in the tunnel where the radio connection appears to be lost. Alvin decided to count those points and found there were exactly 400 points. (ii) Assuming that the tunnel is perfectly straight, calculate the distance between the first and the last point where the radio connection is lost. [2] (b) The apparatus illustrated in Fig. 4.1 is used to demonstrate two-source interference using light. Fig. 4.1 (not to scale) For a particular experiment, red light of λ = 690 nm is used, with a = 0.333 mm and D = 1.20 m. (i) Calculate the fringe separation. [2]