Abstract: In the experiment measuring materials of Young＇s modulus using stretched method, its diametergradually decreases along with the length of it gradually stretches, so one needs to consider this problem. Taking the measurement of Young＇s modulus of the silica gel as an example, we convert the change of its diameter to its elongation. The experimental results of introducing Poisson＇s ratio show that the uncertainty decreases and the accuracy is improved.

Key words: stretched method, Young＇s modulus, Poisson＇s ratio