# Waves Essay

7638 Words31 Pages
1. Water waves at the surface of a pond pass a floating log of length L. The log is at rest relative to the bank. The diagram shows wave crests at one instant. The number of crests passing the log per unit time is N. The speed of the water waves relative to the log at rest is A. (N – 1). B. (N – 1). C. (N) D. (N). (1) 2. Two identical triangular pulses of amplitude X travel toward each other along a string. At the instant shown on the diagram below, point M is midway between the two pulses. The amplitude of the disturbance in the string as the pulses move through M is A. 2X. B. X. C. D. 0. (1) 3. A person is walking along one side of a building and a car is driving along another side of the building. The person can hear the car approach but cannot see it. This is explained by the fact that sound waves A. travel more slowly than light waves. B. are diffracted more at the corner of the building than light waves. C. are refracted more at the corner of the building than light waves. D. are longitudinal waves. (1) 4. A pulse is sent down a string fixed at one end. Which one of the following diagrams best represents the reflected pulse? (1) 5. Waves can be reflected, refracted and diffracted. Which of these effects can be explained using Huygens’ principle? A. reflection, refraction and diffraction B. reflection and refraction only C. refraction and diffraction only D. reflection and diffraction only (1) 6. This question is about waves and wave properties. (a) By making reference to waves, distinguish between a ray and a wavefront. ..................................................................................................................................... .....................................................................................................................................