一弹簧原长为0.12m，用弹簧吊起一物体时，它的长度增至0.17m；再_爱下问搜题

搜题请搜索小程序“爱下问搜题”

问题填空题

一弹簧原长为0.12m，用弹簧吊起一物体时，它的长度增至0.17m；再用该弹簧沿水平方向拉此物体匀速前进时，弹簧长0.135m．由此可知物体和地面间的动摩擦因数为________．

答案

___0.3___

阅读理解

	President Hu Jintao flew to the earthquake-hit region in Yushu, Qinghai on April 18, 2010. At a field hospital on the grounds of a sports stadium, Hu sat on the bed of Drolma, a middle school student, and held her in his arm as she wept(哭泣). “Rest assured(放心的), you will have a full recovery(康复). Be strong. You will have a bright future,” he told her.
The 2010 World Expo, Shanghai China	The 2010 World Expo Shanghai China Duration(举办时间): May 1 to October 31, 2010 Expected visitors: 70 million Theme(主题) : “Better City, Better Life.” The theme represents the common wish of the people all over the world for a better living in future urban(城市的) environments.
	The 19^th FIFA World Cup(世界杯足球赛) Duration: June 11 to July 12, 2010 Host(主办) nation: South Africa Number of teams: Thirty-two Number of matches: Sixty-four It is the first time that the tournament(锦标赛) has been hosted by a nation in the Confederation(联盟) of African Football.

小题1:President Hu Jintao flew to Yushu, Qinghai _________, 2010.

C．on April 18

小题2: President Hu Jintao comforted(安慰) _________ at a field hospital.

A．a middle school student	B．a soldier
C．a farmer of Yushu	D．a doctor

小题3: The 2010 World Expo in Shanghai will end on _________.

A．September 30

C．November 30

D．December 31

小题4:The theme of Expo 2010 is “_________”

A．Better City, Bright future.	B．Better City, Good Environment.
C．Better City, Better Life.	D．Better City, Best Investment(投资).

小题5: There will be _________ teams taking part in the 19^th FIFA World Cup.

问答题简答题

日用瓷生产中常用什么长石？建筑陶瓷生产中常用什么长石？为什么？