5. Explain what the website means when it says Waves transfer energy, not matter.

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1 Introduction When it comes to waves, there are so many ways that waves can be talked about. Whether we are talking about the anatomy of a wave, the different classifications of waves (and there are several!) or the application of waves, the discussion of waves seems to be never-ending and always intriguing. In this mini web-quest, you will navigate to different websites to focus in on these many wave characteristics. We will first start off with a general discussion of waves, then move into light waves & sound waves more specifically, as well as talk about some examples and real-world applications of waves along the way. Waves General Properties Visit the following website and answer the questions below: o 1. According to the above website, what is the definition of a wave? 2. Define equilibrium or rest position. 3. Define disturbance. 4. Define medium. 5. Explain what the website means when it says Waves transfer energy, not matter.

2 Types of Waves When it comes to classifying waves, there are many ways depending on what your focus is. One way to classify waves is to classify by medium in which they travel. In this category there are TWO MAIN CLASSIFICATIONS (though there are more than two): o Mechanical Waves: These are waves that NEED a medium to transfer through. o Electromagnetic Waves: These are waves that DO NOT NEED a medium to transfer through. In this section, we are going to be classifying waves in terms of orientation of change (in other words, how the energy propagates matter as it travels). Visit the following website and answer the questions below: o 1. In a transverse wave, how do the particles move relative to the energy propagation (transfer)? 2. In a longitudinal wave, how do the particles move relative to the energy propagation (transfer)? To make sure you have a good visual, visit the 2 websites below. After, draw a picture of each type of wave mentioned above. Then below each picture, use the 3 rd website to give three (3) examples of each type of wave. o o o TRANSVERSE WAVE LONGITUDINAL WAVE

3 The Anatomy of a Wave Depending on what type of wave you are looking at, the terminology varies a bit. However, the concept is still the same for the anatomy of a wave. Visit the following website to discover the anatomy of a transverse wave and the anatomy of a longitudinal wave. Then answer the questions below: o 1. Below is a labeled transverse wave. For each letter, give the term and a brief definition of each part. C A A: B: D E C: D: B E: 2. Below is a labeled longitudinal wave. For each letter, give the term and a brief definition of each part. A B C A: B: C:

4 The Math Behind Waves One of the benefits of physics is being able to quantify physical phenomena. Waves is not exempt from this. In this section, we will look at some more wave terms and be able to calculate some simple things with waves. Visit the following website and answer the questions below: o Wave 1. Define frequency. Give one example to help explain. What is frequency measured in? 2. Define period. Give one example to help explain. What is period measured in? 3. What is the equation to find frequency? What is the equation to find period? 4. It is recorded that 24 waves pass a point in 7.55 seconds. What is the period? What is the frequency? 5. After 3.00 seconds have passed, 5.50 waves have passed through a certain point. What is the period? What is the frequency? 6. What is the mathematical relationship between frequency and period?

5 Visit the following website and answer the following questions: o 1. What is the equation to find the speed of a wave? 2. A slinky is moved in such a way that it creates a transverse wave. The wave is described as having a vertical distance of 48 cm from a crest to a trough, a frequency of 3.5 Hz, and a horizontal distance of 52 cm from a crest to the nearest trough. Determine the amplitude, period, wavelength, and speed of such a wave. 3. Water waves are observed to have a vertical distance from high point to low point of 5.3 meters and a horizontal distance of 9.5 meters between adjacent crests. The waves splash into the shore every 7.1 seconds. Determine the frequency and speed of these waves. Standing Waves Visit the following website then answer the questions below: o Waves 1. How is a standing wave different from a travelling wave? View the animation at the bottom of the screen and then use it to answer these questions: 2. What is a node? 3. What is an anti-node?

6 4. Below is a standing wave. How many nodes and anti-nodes are there? # of nodes: # of anti-nodes: Wave Interference So what happens when waves come in contact with one another? That is where we have something called interference. Interference has many applications to our world and how we intercept waves. Below is a brief overview of interference. Visit the following website and then answer the questions below: o 1. What are the 2 types of interference? Draw a picture of both (a before and after will be needed for each to show each type) o ce.html The above website shows 2 waves: wave A (blue) and wave B (red). The resulting wave after interference is in white. Play around with the simulation to see the difference between both types of interference. (Pressing pause allows you to see the interference more clearly) Light Waves & Sound Waves Our last section will cover a very brief synopsis of light waves and sound waves, which are really just examples of the types of waves we ve covered so far. Use the internet on your own this time to answer the following questions about light and sound.

7 1. Out of the 2 main types of waves we ve talked about, which one does a light wave fall under? 2. What broad category (that includes 7 sub-categories) does light belong to? 3. What are the 7 categories of light? 4. What is the speed of light? (in m/s) 5. If a light wave has a wavelength of 590 nm, what is its frequency? (1 nm = 1x10-9 m or 1 m = 1x10 9 nm) 6. A light wave has a frequency of 1.67 x 1016 Hz. What is the wavelength (in nm)? Which of the 7 categories from above does this light wave belong to? 7. When it comes to color, what color has the shortest wavelength? Longest wavelength? 8. Out of the 2 main types of waves we ve talked about, which one does a sound wave fall under? 9. When talking about the pitch of sound, what property of the wave is being fluctuated? 10. When talking about the volume of sound, what property of the wave is being fluctuated? 11. Below, draw a picture of a pleasant sound and noise. (hint: Google image search helps with this)