(6分)图甲为“探究求合力的方法”的实验装置. (1)下列说法中正确的是 A.在

题型:实验题

问题:

(6分)图甲为“探究求合力的方法”的实验装置.

(1)下列说法中正确的是       

A.在测量同一组数据和合力的过程中,橡皮条结点的位置不能变化

B.弹簧测力计拉细线时,拉力方向必须竖直向下

C.和合力的大小都不能超过弹簧测力计的量程

D.为减小测量误差,方向间夹角应为90°

(2)弹簧测力计的指针如图乙所示,由图可知拉力的大小为           N

考点:实验:探究弹力与弹簧伸长的关系实验:探究小车速度随时间变化的规律实验:探究加速度与力、质量的关系实验:探究功与速度变化的关系
题型:实验题

阅读短文,判断正(A)误(B)

      Len was thirty years old, and he had very long hair, He lived in a big city, but one year he did not

find any work there, so he went to a small town and began looking for work there. He went to a lot

of places, but nobody wanted him.

      Then he met an old friend, and this man said to him, "People in this town don't like long hair. Why

don't you go to a barber (理发师) ? He can cut a lot of it off and then you can get some work.."

      Len went to a barber and said, "Please cut most of my hair off." The barber began. He cut and cut

for a long time and then he said to Len , "Were you in the army a few years ago?" "Yes, I was." Len

answered. "Why did you ask that?" "Because I have found your cap," the barber answered.

(     )1. Len was twenty years old.

(     )2. Len had very long hair.

(     )3. Nobody wanted Len for work.

(     )4. Len met an old classmate.

(     )5. The barber cut off a lot of Len's hair.

题型:实验题

在1970年到1980年之间,世界工业的能源消耗量在达到顶峰后下降,1980年虽然工业总产出量有显著提高,但工业的能源总耗用量却低于1970年的水平。这说明,工业部门一定采取了高效节能措施。 最能削弱上述结论的是( )。

A.1970年前,许多工业能源的使用者很少注意节约能源

B.20世纪70年代一大批能源密集型工业部门的产量急剧下降

C.工业总量的增长1970年到1980年间低于1960至1970年间的增长

D.20世纪70年代,许多行业从使用高价石油转向使用低价的替代物

题型:实验题

《绿色建筑评价标准》规定,教室的照明功率密度值应不高于()W/m2。

A.30

B.20

C.18

D.11

题型:实验题

凭借国家信用取得的财政收入是()

A.税收收入

B.公债收入

C.国有资产收益

D.收费收入

题型:实验题

两项交易观点

更多题库