The number of waves passing a point every second is defined as the .......of the wave A speed B amplitude C wavelength D frequency Which one of the following is an example of a longitudinal wave? A A Mexican wave B A note played on a violin C Waves on water D Light waves A region of low pressure in a longitudinal wave is called a ....... A reflection B rarefaction C compression D Concentration QuESTION 2 The diagram below shows a series of compressions and rarefactions travelling through a slinky spring. The position of the compressions and rarefactions is shown every \( 0,25 \mathrm{~s} \). Study the diagram and answer the questions that follow: 2.1 2.2 2.3 2.4 Explain what a rarefaction is? Determine the period of this wave. Determine the wavelength of the wave How far did the first compression travel in \( 1,5 \mathrm{~s} \) ? Calculate the speed of this wave

Certainly! Let's address each of your questions step by step. --- ### **Multiple-Choice Questions** 1. **The number of waves passing a point every second is defined as the .......of the wave** **Options:** - A) Speed - B) Amplitude - C) Wavelength - D) **Frequency** **Answer:** **D) Frequency** **Explanation:** Frequency is defined as the number of wave cycles that pass a given point per second. It is measured in Hertz (Hz). 2. **Which one of the following is an example of a longitudinal wave?** **Options:** - A) A Mexican wave - B) **A note played on a violin** - C) Waves on water - D) Light waves **Answer:** **B) A note played on a violin** **Explanation:** A note played on a violin produces sound waves, which are longitudinal waves. In longitudinal waves, the oscillations occur in the same direction as the wave propagation, involving compressions and rarefactions of the medium. 3. **A region of low pressure in a longitudinal wave is called a .......** **Options:** - A) Reflection - B) **Rarefaction** - C) Compression - D) Concentration **Answer:** **B) Rarefaction** **Explanation:** In a longitudinal wave, a rarefaction is the region where particles are spread apart, resulting in lower pressure and density compared to the surrounding medium. This is contrasted with a compression, where particles are closely packed. --- ### **Question 2: Slinky Spring Wave Analysis** *Note: Since the diagram is not provided, the answers below are based on typical properties of longitudinal waves in a slinky.* #### **2.1 Explain what a rarefaction is.** **Answer:** A **rarefaction** is a region in a longitudinal wave where the particles of the medium are spread apart, leading to a decrease in pressure and density. In the context of a slinky, during a rarefaction, the coils of the slinky move away from each other, creating an area of lower compression compared to the surrounding regions. #### **2.2 Determine the period of this wave.** **Answer:** The **period (T)** of a wave is the time it takes for one complete cycle of the wave to pass a given point. If the diagram shows compressions and rarefactions at intervals of **0.25 seconds**, and assuming a complete cycle consists of one compression and one rarefaction, the period would be: \[ T = 0.25\, \text{seconds (compression)} + 0.25\, \text{seconds (rarefaction)} = 0.5\, \text{seconds} \] **Period (T) = 0.5 seconds** #### **2.3 Determine the wavelength of the wave.** **Answer:** The **wavelength (\(\lambda\))** is the distance between two consecutive points in phase, such as two consecutive compressions or two consecutive rarefactions. If the distance between two compressions in the slinky is measured to be, for example, **1 meter**, then: \[ \lambda = 1\, \text{meter} \] *Note:* Replace the distance with the actual measurement from your diagram. #### **2.4 How far did the first compression travel in \(1.5\, \text{seconds}\)?** **Answer:** To determine the **distance (d)** traveled by the compression in a given time, use the formula: \[ d = v \times t \] Where: - \( v \) = speed of the wave - \( t \) = time traveled Assuming you've calculated the speed in the next part, plug in the values accordingly. For example, if the wave speed is **2 meters/second**: \[ d = 2\, \text{m/s} \times 1.5\, \text{s} = 3\, \text{meters} \] *Note:* Use the actual speed value derived from your calculations. #### **2.5 Calculate the speed of this wave.** **Answer:** The **speed (v)** of a wave can be calculated using the formula: \[ v = \frac{\lambda}{T} \] Where: - \( \lambda \) = wavelength - \( T \) = period From the previous answers: - \( \lambda = 1\, \text{meter} \) (replace with actual value) - \( T = 0.5\, \text{seconds} \) \[ v = \frac{1\, \text{meter}}{0.5\, \text{seconds}} = 2\, \text{meters/second} \] **Speed (v) = 2 meters/second** *Ensure to use the actual wavelength and period values from your specific diagram to calculate the accurate speed.* --- **Summary of Answers:** 1. **Frequency** (D) 2. **A note played on a violin** (B) 3. **Rarefaction** (B) For the slinky spring wave: - **2.1:** A rarefaction is a region of lower pressure where particles are spread apart. - **2.2:** Period \( T = 0.5 \) seconds - **2.3:** Wavelength \( \lambda = 1 \) meter (example) - **2.4:** Distance traveled \( d = 3 \) meters (example) - **2.5:** Speed \( v = 2 \) meters/second (example) *Ensure to adjust the numerical answers based on the specific measurements from your diagram.*