How to use dynamometer correctly

Using the elasticity of metal, an instrument marked with scales is made to measure the force, which is called "dynamometer". Dynamometers have various structural forms, but the first part of them is a bent and elastic steel sheet or a spiral tension spring. When the elastic steel plate or tension spring is deformed by external force, the pointer is driven to roll through transmission organizations such as levers, and the position where the pointer stops on the dial is the value of the external force.

1. Before use, investigate whether the pointer is aligned with the zero scale. If it is not aligned with zero, adjust the pointer to zero (or write down the scale to which the pointer is aligned at this moment). Hang the tension spring scale on the iron shelf, pull the tension spring scale by hand (don't pull the pointer to the full scale), and after letting go, investigate whether the pointer returns to zero.

2. When measuring the force, let the line of action of the force be in a straight line with the axis of the tension spring.

3. When reading, the pointer approaches the value of which scale line to read.