Biosystems & Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, 1749-016, Lisboa, Portugal.
Departamento de Física, Faculdade de Ciências, Universidade de Lisboa, 1749-016, Lisboa, Portugal.
Sci Rep. 2017 Jun 16;7(1):3726. doi: 10.1038/s41598-017-03999-w.
Sliding friction is ubiquitous in nature as are harmonic oscillators. However, when treating harmonic oscillators the effect of sliding friction is often neglected. Here, we propose a simple analytical model to include both viscous and sliding friction in common harmonic oscillator equations, allowing to separate these different types of dissipation. To compare this model with experimental data, a nanometric vibration was imposed on a quartz tuning fork, while an atomic force microscope tip was used to disturb its motion. We analyzed tuning fork resonance and 'ring down' experimental curves and for each case calculated the amount of sliding friction and of viscous damping, finding an agreement between the two different experiments and the model proposed.
滑动摩擦在自然界中无处不在，就像谐波振荡器一样。然而，在处理谐波振荡器时，通常会忽略滑动摩擦的影响。在这里，我们提出了一个简单的分析模型，将粘性摩擦和滑动摩擦都包含在常见的谐波振荡器方程中，从而可以将这些不同类型的耗散分开。为了将该模型与实验数据进行比较，我们在石英音叉上施加了纳米振动，同时使用原子力显微镜探针来干扰其运动。我们分析了音叉共振和“衰减”实验曲线，并为每种情况计算了滑动摩擦和粘性阻尼的量，发现两种不同的实验与所提出的模型之间存在一致性。
