人教社２００１年版初级中学物理课本第一册第３１页中，通过敲响音叉后，用悬吊着的泡沫塑料接触发声的叉股，叉股将泡沫塑料球弹开，表明一切发声的物体都在振动。经课堂实践感到泡沫塑料弹开幅度小，后面的同学观察不到。为了弥补上述不足，我们利用光杠杆放大原理，进行了? In the 31st volume of the first edition of the Physics Education Textbook for Junior High Schools 2001 edition of the People’s Education Society, after the tuning fork was touched, the sounding prongs were contacted with the suspended foam, and the prongs bounced off the foam ball to indicate all sounding objects. It’s all vibrating. After the classroom practice, I felt that the foam popping was small, and the students behind could not observe it. In order to make up for the above deficiencies, we used the principle of optical leverage amplification.