Striking Element : It has a hemispherical face of radius 10 mm, made of Teflon, weighing 0.15 Kg.  Steel Tube : It has external diameter – 9mm, and thickness – 0.5 mm. Steel tube is pivoted at its upper end in such a way that it swings only in the vertical plane of the axis of the striking element. The design of the apparatus is such that a force between 1.0 N to 2.0 N is applied to the face of the hammer to maintain the pendulum in horizontal position. Striking Element is rigidly fixed to the lower end of the steel tube.

Striking Element : It has a hemispherical face of radius 10 mm, made of Teflon, weighing 0.15 Kg.  Steel Tube : It has external diameter – 9mm, and thickness – 0.5 mm. Steel tube is pivoted at its upper end in such a way that it swings only in the vertical plane of the axis of the striking element. The design of the apparatus is such that a force between 1.0 N to 2.0 N is applied to the face of the hammer to maintain the pendulum in horizontal position. Striking Element is rigidly fixed to the lower end of the steel tube.