某实验小组在测滑轮组机械效率的实验中得到的数据、实验装置如图所示：

                                                                                                                                                                                                                                      

实验次数	钩码重G/N	钩码上升高度h/m	绳端拉力F/N	绳端移动距离s/m	机械效率η
1	4	0.1	1.8	0.3	74.1%
2	4	0.1	1.6	0.4	62.5%
3	6	0.1	2.4	－	－