🔍 Key Concepts
• Recognize this as a type of steam/air whistle that uses a vibrating element to create pressure waves (sound)
• Identify which labeled part actually moves back and forth rapidly to disturb the air/steam, versus parts that only guide or admit the flow
• Remember that sound requires a periodic vibration, not just a steady flow
💭 Think About
• Which component in the figure is shaped and positioned like a diaphragm or reed that could flex rapidly when steam/air passes?
• Does the device need any part to rotate to make sound, or is it more likely using a thin plate or edge to vibrate?
• If steam or air only rushes in through a port, what must it act upon in order to convert that steady flow into an audible tone?
✅ Before You Answer
• Identify which part (A, B, C, etc.) is the thin, flexible element mounted so it can vibrate when pressure changes
• Confirm that the part you choose for the action (vibrating, rotating, oscillating, or input flow) is actually the one that would periodically disturb the air/steam
• Make sure you are not picking a part that is primarily a housing, cover, or inlet/outlet passage, which by itself would not generate sound