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[Zhejiang University] Doppler Effect Comprehensive Experimental Device
**Doppler Effect Comprehensive Experimental Device**
The Doppler Effect is a fundamental concept in physics, and this comprehensive experimental device is designed to help students explore its principles through hands-on experiments. It enables the accurate measurement of sound speed and object movement, while also verifying the Doppler effect theoretically and practically.
Currently, most available instruments are limited to demonstrations rather than full-scale experiments. This device addresses those limitations by offering a reliable, user-friendly platform that allows for precise measurements and flexible parameter adjustments. Students can conduct various experiments, such as changing signal frequencies, adjusting car speeds and directions, and swapping the positions of the sound source and receiver.
The device consists of three main parts: the host, signal generator/controller, and signal acquisition/processing unit. The host includes a track, stepper motor, belt pulley system, trolley, photoelectric gates, and mounted sound sources or receivers. The signal controller allows for frequency and amplitude adjustments, with digital displays and multiple interface ports for connecting oscilloscopes or computers. The signal acquisition system uses either a computer audio input or an MP3 recorder for data collection and analysis.
This setup supports both uniform and variable-speed motion, and the position of the photoelectric gate can be adjusted for different experiments. The sound source and receiver positions are interchangeable, allowing for both relative and non-relative motion scenarios. The audio signal generator operates between 10 kHz and 20 kHz, ensuring clear, noise-free output.
Through spectrum analysis software, students can process recorded signals to determine frequency shifts, verify the Doppler formula, and calculate the speed of sound and moving objects. The device is not only cost-effective but also highly versatile, making it ideal for university physics labs.
By using this tool, students gain practical insight into wave behavior, improve their analytical skills, and enhance their overall understanding of physical phenomena. It’s an essential resource for modern physics education.
**Completed by: Zhejiang University Physics Experiment Teaching Center**