If you left your book on the table overnight, you would find the following morning that it was still exactly where you had left it, provided nobody had moved it. If a ball is made to roll on a very smooth surface, it will roll a long distance unless something stops it or changes its direction. This tendency of an object to remain at rest unless something moves it and to continue moving unless something stops it is known as the Law of Inertia. The following examples show the truth of this law.
(a) Put a table-cloth on a table and arrange a pile of books on it. Hold one edge of the table-cloth and pull it quickly. The table-cloth will come off, leaving the pile of books undisturbed.
(b) Place a small piece of cardboard on an open jar and place a coin on it directly over its mouth. Use one finger to flick the piece of cardboard away. You will notice that the coin drops into the jar.
(c) Sitting in a car which starts suddenly, you feel you are jerked backwards
A. at rest
B. left behind
C. jerked forward
D. jerked backwards
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[单选题]A-D-B-007 5 2 2
曲线未被平衡欠超高困难情况下不大于( )mm。 A.30 B.50 C.75 D.90 [判断题]有形席位采用场内报盘方式，即由证券公司在柜台接到投资者的委托指令并审查后，以电话方式向“红马甲”转达买卖指令；交易员接到指令后，将指令内容输入证券交易所交易系统电脑主机。( )
[单选题]( )是具有中国特色的制度安排, 是社会主义协商民主的重要渠道和专门协商机构。
A.人民代表大会 B.统一战线 C.人民政协 D.民族委员会 [简答题]简述范仲淹限制君权，“君臣共理天下”的主张
[多项选择]影像板的组成包括（）
A. 板基 B. 光电阴极 C. 荧光体层 D. 保护层 E. 输出屏 [单项选择]预防肾综合征出血热，下列哪项是关键性措施（）
A. 防鼠、灭鼠 B. 注射球蛋白 C. 预防接种 D. 防螨、灭螨 E. 防止皮肤破损 [填空题]铁路线路分为正线、站线、段管线、岔线、()及避难线。
[单选题] 下列送达不属于直接送达的是( )。
A.消防救援机构将行政处罚决定书宣告后当场交付被处罚人王某签收 B.消防救援机构送达处罚决定书时,被处罚人王某不在,由王某妻子签收 C.消防救援机构送达处罚决定书时,被处罚单位的收发室予以签收 D.消防救援机构送达处罚决定书时,被处罚人拒绝签收,将决定书留在受送达人住所 我来回答: 提交
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