摘要
当一线圈悬挂于铜丝下,会因受到铜丝的扭转力矩而作简谐振动,测量简谐振动周期可以计算出铜丝的剪切模量.线圈通电后,因处于地磁场中而受到地磁力矩,利用光杠杆放大原理,只要测量出线圈通电前后的微小偏转角度,也可计算出铜丝的剪切模量.为了减少测量时间,只要将捕捉到的线圈通电前后的简谐振动图像进行图像数值分析,便可在非常短的时间内测量出线圈偏转角度,达到即时测量铜丝的剪切模量.利用运动学、力学、光学、电磁学原理及图像分析技术综合方法测量材料的剪切模量,既提高了测量精度,又降低了测量成本,易于操作,非常适合在大学物理教学中推广.
When a coil hanging under the copper wire, due to the torque of the copper wire for harmonic vibration, simple harmonic vibration cycle can be calculated for the shear modulus of copper wire. After the coil is energized, it is affected by the geomagnetic moment in the earth＇s magnetic field. By using the optical lever amplification principle, the shear modulus of the copper wire can be calculated by measuring the small deflection angle before and after the coil is energized. In order to reduce the measurement time, the coil can be measured in a very short time by measuring the harmonic vibration image before and after the captured coil is energized, so as to measure the shear modulus of the copper wire. The method of kinematics, mechanics, optics, electromagnetism principle and image analysis technique is used to measure the shear modulus of the material, which improves the measurement accuracy, reduces the measurement cost and is easy to operate. It is very suitable for popularization in university physics teaching.
作者
夏雨晴
叶晨钰
王彦昭
张雅男
XIA Yu-qing YE Chen-yu WANG Yan-zhao ZHANG Ya-nan(School of Physics and Optoelectronics Engineering, Nanjing University of Information Science and Technology, Nanjing, Jiangsu 210044, China)
出处
《大学物理》
北大核心
2017年第10期61-64,共4页
College Physics
关键词
扭转力矩
简谐振动
光杠杆
地磁场
图像分析技术
Torsional moment
simple harmonic vibration
optical lever
geomagnetic field
image analysistechnique
