Experiment 7 Standing wave experiment on the string
【Purpose requirement】
1. Observe the standing wave phenomenon formed on the strings fixed at both ends to understand the conditions for the strings to reach resonance and form a stable standing wave;
2. Determine the propagation speed of the transverse wave on the string;
3. Use the experimental method to determine the relationship between the resonance frequency and the tension when the string is forced to vibrate;
4. Use logarithmic drawing and least squares method to linearly fit the experimental results of the relationship between resonance frequency and tension, process the data, and give conclusions.
【Experimental Principle】
Tighten the A and B strings of both ends of a string with a certain tension. At this time, if there is a driving source between the A and B end points to make the string line undergo a simple harmonic vibration with constant amplitude near the A end, if there is a certain relationship between the length of the string line and the wavelength, some points will occur on the string The amplitude of the vibration is the largest, called the antinode; while the amplitude of some other points is zero, called the node, forming a standing wave phenomenon.
【Experiment content】
1. Recognize and adjust the instrument;
2. Determine the linear density of the strings used;
3. Observe the standing wave on the string;
4. Determine the propagation speed of the transverse wave on the string;
5. Determine the relationship between the resonance frequency and tension when the string is forced to vibrate.
【Instruments】
Serial number
equipment name
Model / Specification
Unit price (yuan)
Remarks
1
String vibration research experiment instrument
DH4618
3350
Including signal source, drive coil, detection coil
2
Weight
1kg
3
String
6 of different linear density
4
Screw caliper
LZ-1 / 0 ～ 25mm, 0.01mm
5
Level bubble
6
Dual Trace Oscilloscope
MOS620CH / 20MHz
1800
Can choose one
Digital storage oscilloscope
TH1022A / 25MHz
2450
