RI Y6 Remedial Oscillations and Wave Assignment

Raffles Institution Year 5-6 Physics Department 1 2025 Year 6 H2 Physics Remedial Chapter 10: Oscillations 1 The graph shows the variation of acceleration a with displacement x for an object undergoing simple harmonic motion. The simple harmonic motion system is altered so that it has a period half of that before. Which line shows the new variation of acceleration a with displacement x for the object? [ACJC/Prelims 2014/P1/18] 2 The diagram shows the graph of velocity against time for a body performing simple harmonic motion. At which point are the velocity and acceleration in opposite directions? [DHS/Prelims 2014/P1/15] time velocity A B 0 C D

Raffles Institution Year 5-6 Physics Department 2 3 The arrangement shown in Fig. 1.1 is used to determine the length x of a spring when different masses M are attached to the spring. Fig. 1.1 The variation with length x of mass M is shown in Fig. 1.2. Fig. 1.2 (a) State the natural length of the spring. [1] (b) Use Fig. 1.2 to determine the spring constant of the spring. [2] A mass m is then attached to the spring. The mass is displaced vertically then released. The variation with time t of the displacement y from its mean position is shown in Fig. 1.3. spring mass x x / cm M / kg 70 65 60 55 50 45 75 0 0.20 0.40 0.60

Raffles Institution Year 5-6 Physics Department 3 Fig. 1.3 (c) Calculate the angular frequency of the oscillation. [1] (d) The spring-mass system undergoes free oscillations. (i) Explain what is meant by free oscillations. [1] (ii) Determine the mass m that results in the oscillations shown in Fig. 1.3. [2] (iii) Hence or otherwise, find the length x of the spring at y = 0 cm. [1] [DHS/Prelims 2014/P3/1] 4 A mass of mass m was suspended from the bottom of a vertical spring, and set into oscillation with a period T. Measurements were made, and the resultant force F acting on the mass, and its velocity v were obtained. The graphs below were then plotted to show how F and v vary with the displacement x of the mass from its equilibrium position. Calculate: (a) the period of the oscillation, and (b) the mass m. [4] [VJC/Prelims 2014/P2/1] y / cm 0 t / s 0.25 0.50 0.75 1.00 1.25 1.50 0 F/ N x/m 0 0.45 -0.45 0.63 -0.63 v/ m s-1 x/m 0 0.45 -0.45 1.2 -1.2

Raffles Institution Year 5-6 Physics Department 4 Chapter 11: Wave Motion 1 The figure below shows the positions of a travelling wave at time intervals t = 0 and t = 2 s. Calculate the speed of the wave. A 0.5 cm s−1 B 2.0 cm s−1 C 0.5 m s−1 D 2.0 m s−1 [JJC/Prelims 2014/P1/25] 2 The diagram shows a transverse wave on a rope. The wave is travelling from left to right. At the instant shown, the points P and Q on the rope have zero displacement and maximum displacement respectively. Which of the following describes the direction of motion, if any, of the points P and Q at this instant? point P point Q A downwards downwards B downwards stationary C upwards downwards D to the right to the right [NYJC/Prelims 2014/P1/19]

Raffles Institution Year 5-6 Physics Department 5 3 The figure below shows two ideal polarisers A and B where their transmission axes are initially parallel to each other. Polarised light of amplitude E0 and intensity I0 is incident on A with its electric field vector parallel to the transmission axis. Polariser B is then rotated so that its transmission axis makes an angle θ, as shown in the figure above. Which of the following graphs shows how the intensity of the transmitted light It varies with the angle θ? A B C D [CJC/Prelims 2014/P1/20] 4 Alice is standing 15 m away from a speaker listening to a music broadcast. Due to a technical fault, the power of the speaker is suddenly reduced by 25%. How far away from the speaker should Alice stand now in order for the music to be as loud as before? Assume that the speaker is a point source of sound. A 13 m B 11 m C 7.5 m D 3.8 m [MJC/Prelims 2014/P1/17]

Raffles Institution Year 5-6 Physics Department 6 5 Fig. 8.1 shows the variation with time t of the displacement DA and DB at a point X of two sound waves A and B. Fig. 8.1 (a) By reference to Fig. 8.1, state one similarity and one difference between these two waves. [2] (b) State, with a reason, whether the two waves are coherent. [1] (c) The intensity of wave A alone at point X is I. (i) Determine the intensity of wave B alone at point X. [2] (ii) Determine the resultant intensity of the two waves at point X. [RVHS/Prelims 2014/P3/8 Part] [2] Wave A Wave B t / 10─4 s t / 10─4 s DB DA