### Mechanics

Example of experimental results

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## LEMI-53 Apparatus of Sound Speed Measurement & Ultrasonic Ranging

Features

• High performance ultrasonic sensor

• Simple structure, stable and reliable

• Multiple experiments

Introduction

The propagation speed of sound waves is an important physical quantity. The measurement of sound speed is widely applicable in ultrasonic ranging, positioning, measurement of liquid flow rate, material's elastic modulus and changes of gas temperature. Ultrasonic emission and reception is also one of the important means of anti-theft, monitoring and medical diagnosis.

This experimental apparatus of sound speed measurement and ultrasonic ranging is specially designed for educational training in teaching labs. It can measure the speed and the wavelength of a sound wave propagating in the air, and perform an experiment on ultrasonic ranging, so that students can better understand the basic principles and experimental methods of wave physics.

LEMI-53 apparatus has the following features:

1. A compact high efficient ultrasonic sensor is used. It has a metal housing shield of strong anti-interference ability with strong reflection and reception signal;

2. The apparatus is simple in structure, easy in operation and reliable in data reading.

Using this apparatus, the following experiments can be conducted:

1. Measure the speed of sound wave propagating in the air by the method of resonant interference.

2. Measure the speed of sound wave propagating in the air by the method of phase comparison.

3. Measure the speed of sound wave propagating in the air by the method of time difference.

4. Measure the distance of a barrier board by the method of reflection.

Parts and Specifications

 Description Specifications Sine wave signal generator: Frequency range: 30 ~ 50 kHz; resolution: 1 Hz Ultrasonic transducer Piezo-ceramic chip; oscillation frequency: 40.1 ± 0.4 kHz Vernier caliper Range: 0 ~ 200 mm; accuracy: 0.02 mm Experimental platform Base board size 380 mm (L) × 160 mm (W) Measurement accuracy Sound velocity in air, error < 2%

Example of experimental results

(Click to enlarge)