• Free vibration of a vertical bending bar.
  • Determination of natural frequencies according to Rayleigh.
  • Influence of free clamping length and weight on natural frequency.


  • Investigation of the free vibration of a bar.
  • Elastic bending bar with movable weight.
  • Inductive position sensor to measure oscillation amplitudes.
  • Fixable meter rule.

This unit is designed to study the characteristics free vibration of a bending bar. When a bar is loaded with some weight and given a deflection, it starts oscillating. The time period and frequency of oscillation depends on the mass and dimensions of the bar. The unit consists of a rectangular frame on which the bar can be placed in any direction. The bar is fixed at one end and mass is added on bar at other end. The unit contains a proximity sensor as well which measures the time period and frequency of the vibrating bar. The waveform of the vibration can be seen by oscilloscope. The bending bar in can be mounted vertically (standing or hanging) or horizontally into the frame. By varying the free clamping length or moving additional weights, the natural frequency of the bar is changed. The bar is deflected manually to start damped vibrations. A non-contact position sensor measures the corresponding amplitudes.