H211 Wave Motion - 2. Tutorial (1718)

Topic 11: Waves Page 1 of 6 9749 H2 Physics Tutorials Tutorial Topic 11: Waves Properties of Waves 1. (a) Distinguish between longitudinal and transverse waves. (b) What are some of the phenomenon that is associated with transverse waves but is not observed with longitudinal waves? (c) Fig. 1 shows 2 graphs which refer to the same wave. Calculate the speed of the wave Fig. 1 2. During a lab demonstration, 2 set of ripple tanks and wave generators are being set up in the lab and activated. Water waves having a wavelength of 0.05 m are being generated in both tanks. 2 p olystyrene balls A and B are then placed respectively in each tank and have their motions being tracked using a software. The displacement - time graph of the balls are being plotted as shown in Fig. 2. Fig. 2 (a) State which of these term(s): period, frequency, angular frequency and amplitude will be the same between the oscillations of A and B. (b) Determine the period of oscillation for particle B. (c) Determine the speed of the wave that is being generated in the ripple tank. (d) Calculate the speed with which B is traveling at the point marked P. (e) Calculate the phase difference between the oscillations. (f) Write an equation for the oscillation of A to show how x is related to t.

Topic 11: Waves Page 2 of 6 9749 H2 Physics Tutorials 3. Parallel water waves travelling with a velocity of 2.0 m s-1 and a frequency of 10 Hz strike a straight wall as shown in Fig. 3. The wavefronts make an angle of 60° with the wall as shown. What is the phase difference between two points 5.0 cm apart along the wall? Fig. 3 4. Fig. 4a below shows an instantaneous position of a string as a transverse wave travels along it from left to right. Fig. 4a (a) Draw arrows on Fig. 4a to indicate the directions of the velocities of the points 1, 2 and 3 on the string. (b) Fig.4b show a progressive transverse and a progressive longitudinal wave respectively. Fig. 4b On each of the diagrams above, identity a point or points at which (i) the velocity is zero. (ii) the acceleration is zero. (iii) the velocity is in the same direction as the displacement. (iv) the acceleration is in the same direction as velocity. x 1 2 3

Topic 11: Waves Page 3 of 6 9749 H2 Physics Tutorials Energy and Intensity 5. A satellite passing the planet Neptune communicates with its controller on the Earth using a microwave transmitter with output power 22.0 W and wavelength 79 600 m. Neptune is 4.35 × 1012 m from the Earth at the time when the communication takes place. (a) Calculate the time taken for a signal to travel from the satellite to the Earth. (b) Assuming that the power transmitted by the satellite is radiated uniformly in all directions, calculate the power received on the Earth by a dish aerial of effective area 260 m2. (c) The actual power received at the di