HCI Worksheet 15 Waves

Hwa Chong Institution Sec 3 Physics 1 Name: _________________________________________ Class: ___________ Date: ______________ Sec 3 Physics (SSMT / IP) Worksheet 11: Waves 1 Water waves were produced in a ripple tank using a vibrator of frequency of 3 Hz. Which of the following values of speed and wavelength could the waves have had? speed wavelength A 1 cm/s 3 cm B 2 cm/s 1 cm C 5 cm/s 15 cm D 12 cm/s 4 cm [ ] 2 A wave source of 1000 Hz emits waves of wavelength 0.1m. How long does it take for the waves to travel 2500 m? A 4 s C 40 s B 25 s D 100 s [ ] 3 The table shows examples of transverse and longitudinal waves. Which line in the table is correct? transverse longitudinal A gamma rays sound B infra-red radio C infra-red water waves D radio light [ ] 4 The diagram shows a ball floating in a tank of water. Which diagram shows the movement of the ball when the wave passes? [ ]

Hwa Chong Institution Sec 3 Physics 2 5 A long rope is stretched out on the floor. One end of the rope is then shaken. The graph shows the rope at a particular moment in time. Which is the wavelength of the wave motion? A 0.36 m C 0.8 m B 0.6 m D 1.6 m [ ] 6 The diagram shows how displacement varies with time as a wave passes a fixed point. What is the frequency of this wave? A 0.25 Hz C 1.0 Hz B 0.50 Hz D 2.0 Hz [ ] 7 The diagram shows a cross-section of a water wave. Which distance is the amplitude of the wave? [ ] E

Hwa Chong Institution Sec 3 Physics 3 8 A lightly coiled spring is fixed at one end and held by hand at the other. Which hand movements cause first a compression and then a rarefaction to travel along the spring? A down then up B up then down C left then right D right then left [ ] 9 A transverse wave travels from left to right. The diagram shows at a particular instant of time, the displacement of particles in the medium varies with position. Which arrow represents the direction of the velocity of the particle marked P? [ ] 10 Light travels from air into glass, as shown below.

Hwa Chong Institution Sec 3 Physics 4 What is the refractive index of glass? A B C D [ ] 11 Which of the following electromagnetic waves has a frequency greater than visible light? A Ultraviolet B Radio C Microwaves D Infrared [ ] 12 A particle oscillates with simple harmonic motion with period T. At time t = 0, the particle has its maximum displacement. Which graph shows the variation with time t of the kinetic energy Ek of the particle? [ ] S P sin sin R Q sin sin R P sin sin S Q sin sin

Hwa Chong Institution Sec 3 Physics 5 13 The graph shows the height h of sea level at different times t in the Bay of Fundy. Which of the following gives the approximate amplitude and period of the tides? Amplitude Period A 6.5 m 6 hours B 13 m 12 hours C 6.5 m 12 hours D 13 m 6 hours [ ] 14 Which of the following is a wavelength value found in the visible region of the electromagnetic spectrum? A 4 × 10 –5 m B 4 × 10 –7 m C 4 × 10 –9 m D 4 × 10 –11 m [ ] 15 Two waves meet at a point in space. Which of the following properties always add together? A Displacement B Amplitude C Speed D Frequency [ ]

Hwa Chong Institution Sec 3 Physics 6 16 The diagram below is a snapshot of wavefronts of circular waves emitted by a point source S at the surface of the water. The source vibrates at a frequency f = 10.0 Hz. The speed of the wavefront is A 0.15 cm s –1 . B 1.5 cm s –1 . C 15 cm s –1 . D 30 cm s –1 . [ ] 17 Two coherent point sources, S1 and S2, emit spherical waves.

Hwa Chong Institution Sec 3 Physics 7 Which of the following best describes the intensity of the waves at P and Q? P Q A maximum minimum B minimum maximum C maximum maximum D minimum minimum [ ] 18 Monochromatic light travels from air into water. Which of the following describes the changes in wavelength and speed? Wavelength Speed A increases decreases B increases increases C decreases increases D decreases decreases [ ] 19 A wave pulse is travelling to the right along a string. Which of the following best represents the direction of the velocity of the point P? A ↑ B ↓ C → D ←

Hwa Chong Institution Sec 3 Physics 8 STRUCTURED QUESTIONS 1 The figure below shows a student setting up waves on a long elastic cord. The student ’s hand makes one complete up -and-down movement in 0.40s, and in each up -and-down movement, the hand moves through a height of 0.30 m. The wavelength of the waves on the string is 0.80 m. For this wave, determine a Amplitude = b Period = c Frequency = d Speed = [6] e Using a line with arrows on both ends, label the wavelength of the waves in the diagram above. [1] f Label 2 points Y and Z on the line in phase with point X. [2] g Sketch the shape of the waves in real life. [2] 2 Transverse waves are produced in a long rope by securing one end of th e rope to a wall and then moving the other end from side to side by hand. The frequency of the waves is 2 Hz. a How are “transverse waves” different from “longitudinal waves”? [2] 0.30 m X

Hwa Chong Institution Sec 3 Physics 9 b Explain the meaning of the expression “the frequency is 2 Hz”. [1] c What determines the amplitude of the waves produced? [1] 3 Transverse waves of wavelength 40 mm and amplitude 15 mm travel across a liquid surface. a On the grid (2mm) below , draw a full-scale diagram showing a side view of the liquid surface at a particular instant. [2] b If the frequency of vibrations of the waves is 12 Hz, calculate the speed at which they travel across the liquid surface. Speed = ……………………………….. mm s-1 [2]

Hwa Chong Institution Sec 3 Physics 10 4 a Figure 4.1 shows the graph of the displacement of a wave with distance along the wave at a particular time. Figure 4.1 State the values for (i) the amplitude of the wave: m [1] (ii) the wavelength of the wave: m [1] b Figure 4.2 shows the graph of the displacement of the same wave with time at a particular point along the wave. Figure 4.2 State values for (i) Time for one cycle = s [1] (ii) Frequency of the wave = Hz [1] c Calculate the speed of the wave drawn in Figures 4.1 and 4.2. Speed of wave = ……………………………. ms-1 [2] 0 10 0 -0.6 0.6 displacement m distance m 0 2.5 0 -0.6 0.6 displacement m time / s