题目

Taking a shower is relaxing. You can hum a song, daydream or think about nothing, leaving the real world behind you. But did you know that showering can also benefit your mind?     A research by Scott Barry Kaufman, a psychologist from Yale University in the US interviewed over 3,000 people around the world. It turned out that nearly two-thirds of the interviewees said they had experienced new ideas in the shower and were more likely to have them in the shower than at work.     So why does a simple shower have such magic power? Science can explain it. Showering can help to raise 测量小灯泡电功率（小灯泡标有“3.8V”字样）． 实验次数 电压表示数/V 电流表示数/A 灯泡亮度 1 0.5 0.1 不发光 2 2.0 0.25 发光较暗 3 3.8 正常发光 4 6.0 0 不发光       小宇正确连接电路后，闭合开关，记录的部分实验数据和现象如下表所示. （1）分析表中实验数据可知：第1次实验中，小灯泡不发光的原因是                               ，接下来应进行的操作是                           ． （2）由于小宇粗心大意，没有记录灯泡正常发光时电流表的示数，于是他根据第一次实验数据计算出灯泡电阻：R=U1/I1= 0.5V/0.1A=5Ω，再计算出灯泡的额定功率：P＝U23/R =(3.8V)2/5Ω=2.888W．请你对小宇计算额定功率的方法作出评价：小灯泡的额定功率_______（选填“大于”“等于”或“小于”）2.888W，理由是           ．