橡皮筋也像弹簧一样，在弹性限度内，伸长量x与拉力F成正比，即F=kx，下面的表格是张翰做的某橡皮筋受到的拉力F与伸长量x的实验记录。                                                                                                                          

拉力F/N	5	10	15	20	25
伸长量x/cm	1.6	3.2	4.8	6.4	8