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Home Concept Builders Vibrations and Waves Wave Interference Directions

Wave Interference - Directions

Using the Wave Interference Concept Builder is quite simple. There are three different activities; each activity has a different set of tasks to complete.

In the first activity - To Construct or To Destruct? - you will be presented with a diagram of two interfering waves. There are five locations marked along the medium. You will have to identify the type of interference occurring at each location as being an example of constructive interference or destructive interference. You categorize these five locations by tapping on the letter located below the two interference categories. When you tap on a letter, it turns from grey to red with a circle around it. A red letter with a circle around it indicates that that letter has been selected for that particular interference category that it is located under. If you change your mind, then tap on the letter a second time to deselect it or tap on the same letter under the other category. Once you have categorized each of the five locations, a Check Answer button appears. If you are satisfied with your answers, tap on the Check Answer button. Your answer will be evaluated and feedback will be given. The Progress Report will be updated and you will be given a new question.

In the second activity - The Principle of Superposition - you are presented with a diagram of two interfering waves and three marked locations along the medium. For each marked location, you must determine the amount of displacement the medium would experience as a result of the interference of the two waves. Each square on the grid is 0.10 meters in height. Tap on the answer field to select your answer. Answers will toggle through all possible options from 0.9 m to -0.9 m. Once you have selected an option for all three locations, a Check Answer button appears. If you are satisfied with your answers, tap on the Check Answer button. Your answer will be evaluated and feedback will be given. The Progress Report will be updated and you will be given a new question.

In the third activity - Sum It Up - you are presented with a diagram of two interfering waves. You must determine the shape of the resultant wave (or wave sum). You will notice nine dots located above the waves and the background grid. You have to drag each do to the proper location above or below the resting line. If you drag the dot to the right location, then it will snap into place. If it is the wrong location, then the dot will be returned to its initial location and you can try again. Once all dots have been dragged to the proper location, the resultant wave will be drawn through the dots and a Continue button will appear. When tap on the Check Answer button, the Progress Report will be updated and you will be given a new question.

Your goal is to earn "Stars" and to complete one or more activities. Stars are earned when you show success on a particular question. Once you show success on all the questions for a particular activitiy, you will earn the Trophy for that activitiy.

Concept Builder Teacher Notes