题干

小张同学在测量一块形状不规则、体积较大的矿石密度实验中,首先拿出托盘天平放在水平桌面上,并将游码移到零刻度线上后,发现指针偏转如图甲所示.他应采取的措施是使右端的平衡螺母向____ (选填“左”、“右”)移动直到指针指在分度盘的中央,此时天平就平衡 。

(1)用调节好的天平测量矿石的质量,当天平平衡时,右盘中砝码和游码的位置如图乙所示,矿石的质量是____g;

(2)因矿石体积较大,放不进量筒,因此他利用一只烧杯,按如图所示方法进行测量,矿石的体积是____ cm3

(3)矿石的密度是____kg/m3(保留一位小数),从图A到图B的操作引起的密度测量值比真实值____(选填“偏大”、“偏小”、“不变”) 。

上一题 下一题 0.0难度 选择题 更新时间:2018-03-07 07:01:54

答案(点此获取答案解析)

左,176,60 ,2.9×103,偏小

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