皮皮学,免费搜题
登录
搜题
【简答题】
为了模拟研究汽车超载和超速带来的安全隐患,小明同学设计了如图所示的探究实验:将A、B、C三个小球先后从同一装置高分别为h A 、h B 、h C 的位置滚下(m A =m B <m C ,h A =h C >h B ),推动小木块运动一段距离后静止.请你根据生活经验和所学的物理探究方法,对以下问题进行判断: (1)用来研究超载安全隐患时,我们应选择______两个图所示实验进行比较. (2)用来研究超速安全隐患时,我们应选择______两个图所示实验进行比较. (3)实验中让静止的小球从斜面滚下,观察木块被推动的距离.关于该实验的说法中,不正确的是______ A.该实验的设计思路是采用转换法,用木块移动的距离来表示动能的大小 B.该实验研究的基本方法是控制变量法,如分别控制小球滚下的高度、小球的质量等 C.在实验器材的选择时,可以不考虑斜面的光滑程度,被撞木块的质量和软硬等因素 D.实验过程中,让同一小球从不同高度落下,目的是为了让小球获得不同的运动速度.
拍照语音搜题,微信中搜索"皮皮学"使用
参考答案:
参考解析:
知识点:
.
..
皮皮学刷刷变学霸
举一反三
【简答题】你知道的电子商务类型有哪些。请举例说明。
【单选题】— I've started my own software company. —________________
A.
Could you tell me who is the owner?
B.
No kidding! Congratulations!
C.
If I had the money, I'd start one.
【多选题】Choose the expressions to be used a t the start of a meeting.
A.
Let’s call it a day.
B.
Let’s get down to business.
C.
Could you take the minutes?
D.
Is everyone happy with that?
E.
Would you like to kick off then?
F.
That’s a terrible idea!
G.
Let’s move on to the next point then.
【多选题】You are on a bus sitting next to a Western, and you would like to start a conversation with him. Which of the following could you say to start the conversation?
A.
Hello. Where are you from?
B.
It ’ s very hot today, isn ’ t it?
C.
Hello, where are you going?
D.
This bus is crowded, isn ’ t it?
【单选题】患者男性,慢性咳嗽、咳痰反复发作20余年,痰多呈白色黏液样,有时为黄脓痰,近半年来咳痰偶带血丝,逐渐发展为气喘不能平卧,临床检查,呈桶状胸,腹部膨隆,腹水(+),后因呼吸循环衰竭抢救无效死亡。尸检见腹腔内350ml淡黄色积液,肺组织弹性减弱。显微镜下:支气管黏膜上皮脱落,管壁淋巴细胞、单核细胞浸润,部分支气管呈圆柱状,部分呈囊状扩张,累积段支气管以下。病例最有可能的病变发展过程是()
A.
慢性支气管炎,小叶性肺炎
B.
慢性支气管炎,病毒性肺炎,肺气肿,肺源性心脏病
C.
慢性支气管炎,支气管扩张,肺气肿,肺源性心脏病
D.
慢性支气管炎,肺气肿,肺癌,肺源性心脏病
E.
慢性支气管炎,大叶性肺炎,肺气肿,肺源性心脏病
【单选题】韦克斯勒智力量表有 套?
A.
1
B.
2
C.
3
D.
4
【简答题】阅读下面短文,从短文后各题所给的 A 、 B 、 C 和 D 四个选项中,选出最佳选项。 Tom with his axe was stepping through the wood. A sapling( 树苗 ) 41 him on his way, “ Do clear away those trees, kind friend, I wish you 42 ! ” “They will n...
【单选题】— I’m afraid I can’t get up early. You know, winter is coming. Besides, I hate getting up early. ___________. —W ere I you, I’d start from something easy, such as doing some sports once a week at firs...
A.
What time would you like to get up ?
B.
What would you do in my situation ?
C.
Do you agree with me?
D.
Could you change my mind ?
【简答题】Passenger: Uh, how to start? Hum... prefix="o" ns="urn:schemas-microsoft-com:office:office" ?xml:namespace> Clerk: Excuse me. (1) _________ any help? Passenger: No, I...I’m just looking...Uh, well, ac...
【简答题】The first way to make friends is to smile. When you smile, people think you are __1___ and easy to talk to. It may not be easy at first to smile. But, you can practice in the mirror(镜子). When you look...
相关题目: