Wave Properties - Catholic Central School PDF

ORA LABORA STUDE Catholic Central School of Tabaco Albay, Inc. S.Y. 2023-2024 Wave s Prepared by: Laiza M. Belchez You have probably seen a wave, but have you created one? Let’s try and make some waves? Waves - are disturbances that travel through either...

ORA LABORA STUDE Catholic Central School of Tabaco Albay, Inc. S.Y. 2023-2024 Wave s Prepared by: Laiza M. Belchez You have probably seen a wave, but have you created one? Let’s try and make some waves? Waves - are disturbances that travel through either a medium or a vacuum in space, resulting in vibrations or oscillation. When water in the sea or the lakes arches as you swim or glide through it, your are generating a small waves that move outward from your position. Note that energy passing through either a medium or vacuum creates the waves. When the wind blows through the surface of the sea, its energy sends the water in circular motion. Similarly, if you pluck the strings of a guitar or blow through the mouthpiece of a flute, your action produces energy that creates sound waves.  Mechanical Waves – are waves that require a medium or any matter through which energy can travel. Note: The energy vibration of mechanical waves interact with molecules of a medium, which may come in solid, liquid or gaseous form -Sound waves Water Waves Seismic Waves Slinky or spring waves Electromagnetic waves can travel through both matter and vacuum, it is formed through the interaction of electric and magnetic fields. Examples: Radio waves Microwaves Oscillation are continues back-and-forth or side-to-side movements of an object. A wave can produce an oscillation in the particles of the medium through which it travels. When a particles is oscillating towards a direction perpendicular to the direction of the wave, the wave is classified as a transverse wave. Transverse waves oscillate in an alternating upward and downward motion. The peak or highest point of a wave moving upward is known as the crest, while the lowest at each valley of a wave is known as trough. The imaginary horizontal line in the middle of the wave is know as normal line. When the particles of the medium are moving parallel to the direction of the propagation, the wave is considered a longitudinal wave. Consider the oscillations generated along a stretched spring. If the spring is set in back and forth motion, the energy induces a wave that travels from the left to the right of the spring. In effect, each coil in the spring oscillates from the left to the right side as well, creating longitudinal wave, it travels through a solid, liquid, or gaseous medium. TRANSVERSE WAVE VS. LONGITUDINAL WAVE Take note that is some groups of coil are farther apart than others. The coils that appear darker and closer to each other are called compressions. As they are tightly compressed. Oppositely, the coils which have more spaces in between known as rarefactions. Characteristic of Wave Amplitude- of a wave refers to the distance between the normal line and the tip of a crest or a trough. Wave amplitude indicates intensity or brightness of an electromagnetic wave relative to the brightness of another. An electromagnetic wave with higher amplitude is positive if measured from the crest to the normal line and negative if measured from the crest to the normal line, and negative if measured from the trough to the normal line. The crest is the highest point of a wave. A wave can have multiple crests. A crest can be any size, shape, or form. The wavelength of the wave is measured in- between two crests in the wave. The distance between two crest or two troughs is known as the wavelength. Two wave points that are traveling with the same speed, displacement , and height towards the same direction are described to be in phase. The trough is the lowest point of a wave. A wave can have multiple troughs. The trough is in between two crest and is also used to measure the wavelength. The period of a wave refers to the time that one crest or trough complete one cycle, or travels a distance of one wavelength. Period is a measurement of time, and is therefore expressed in units such as second (s), minutes (m), and hours (h). The wavelength determine the period of the wave. Longer wavelengths mean the waves are travelling at a longer period of time, while shorter wavelengths indicate that waves are travelling at a shorter period of time.  Frequency- of a wave is defined as the number of full wavelengths travelling trough point in space per unit time. Frequency indicates how many individual crest troughs are propagated within a second. Frequency is defined as the number of oscillations of a wave per unit of time and is measured in hertz(Hz). 1 It applies the SI unit Hertz (Hz) which was derived from the surname of Heinrich Hertz , the German scientist who confirmed then existence of electro magnetic waves. 1 Hz is equal to one cycle per second. The frequency of a wave is related to its wavelength. Frequency and wavelength are inversely proportional to each other; the shorter the wavelength, the higher the frequency of the wave and vice versa. This relationship is given by the following equation: Assessment: Answer page 93 Let Us Apply A and C PROBLEM SOLVING FOR FREQUENCY, WAVELENGTH AND VELOCITY SAMPLE PROBLEM 1: A wave has frequency of 50 Hz and a wavelength of 10 m. What is the speed of the wave? SOLUTION: SAMPLE PROBLEM 2: A wave has frequency of 5Hz and a speed of 25 m/s. What is the wavelength of the wave? SOLUTION: SAMPLE PROBLEM 3: A wave has wavelength of 10 m and a speed of 340 m/s. What is the frequency of the wave? SOLUTION: SAMPLE PROBLEM 4: What is the wavelength of sound wave that is traveling at 343 m/s and has a frequency of 440 Hz? SOLUTION: SAMPLE PROBLEM 5: A symphony tunes to an oboe playing a note at 430Hz. If the speed of sound is 347.29ms, what is the wavelength of this note? SOLUTION: SAMPLE PROBLEM 6: A note is played with a wavelength of 0.449m. If the speed of sound is 360.29ms, what is the frequency of the note? SOLUTION: SAMPLE PROBLEM 5: A wave with a frequency of 500 Hz is travelling at a speed of 200 m/s. What is the wavelength? SOLUTION: SAMPLE PROBLEM 6: A wave has a wavelength of 125 meter is moving at a speed of 200 m/s. What is the frequency? SOLUTION: SAMPLE PROBLEM 5: A wave with a frequency of 14 Hz has a wavelength of 3 meters. At what speed will this wave travel. SOLUTION: SAMPLE PROBLEM 6: A wave has a wavelength of 930 meter is moving at a speed of 15 m/s. What is the frequency? SOLUTION:  MECHANICAL PROPERTIES OF WAVES  OBJECTIVES : At the end of the lesson, you are expected to: 1. Define reflection, refraction, diffraction, interference. 2. Give sample of the four mechanical wave properties. 3. Appreciate the role of four types of mechanical waves to our day-to-day living. What happen when a type of wave meets its end in the medium? The wave doesn't just stop when it reaches the end of the medium. Rather, a wave will undergo certain behaviors when it encounters the end of the medium. Specifically, there will be some reflection off the boundary and some transmission into the new medium. All waves behave in certain characteristic ways. They can undergo refraction, reflection, interference and diffrac tion. These basic properties define the behavior of a wave – anything that reflects, refracts, diffracts and interferes is labelled a wave. PROPERTIES OF MECHANICAL WAVE 1.Reflection – this behavior exhibits a wave frequency and wavelength are simply mirrored or reflected by the returning wave. 2.Refraction – when a mechanical wave travelling one medium encounters another and bends at a different angle. - In this property, the shift in the medium change wavelength and the frequency of the mechanical wave. When light meets a water droplet, it is refracted at the boundary of air and water , and enter the droplet , where the light dispersed into seven colors. The rainbow effect occurs because the light is then reflected inside the droplet and finally refracted out again into the cycle. 3. Diffraction- a mechanical wave may encounter a barrier with a gap, a hole or a slit. When this happens, the wave passes through the open spaces or travels around the edges of the barrier. Diffraction of light is the bending of light around the corners such that it spreads out and illuminates areas where a shadow is expected 4. Interference. This happens when two waves meet along the same medium. There are two kinds of interference: Constructive and Destructive Constructive A. Constructive Interference- involves the combination of two interfering waves moving towards the same direction. B. Destructive interference -the waves can combine and decrease each other’s amplitudes or cancel each other out. THANK YOU!