问题 实验题

两只相同的烧杯,分别盛有体积相同的水和酒精,但没有标签,小栋采用闻气味的方法判断出无气味的是水.小旭则采用压强计进行探究:

(1)若压强计的气密性很差,用手指不论轻压还是重压橡皮膜时,发现U形管两边液柱的高度差变化________(大/小).小旭把调节好的压强计放在空气中时,U形管两边的液面应该________(相平/不相平).

(2)小旭把金属盒分别浸入到两种液体中,发现图(甲)中U形管两边的液柱高度差较小,认为图(甲)烧杯中盛的是酒精.他的结论是不可靠的,因为没有控制金属盒在液体中的_______相同.

(3)小旭发现在同种液体中,金属盒离液面的距离越深,U形管两边液柱的高度差就越________,表示液体的压强越________(大/小).

(4)小旭还发现在同种液体中,金属盒距液面的距离相同时,只改变金属盒的方向,U形管两边液柱的高度差________(不变/变化).表明在相同条件下,液体内部向各个方向的压强________.

答案

(7分)(1)小   相平   (2)深度

(3)大   大   (4)不变   相等

题目分析:(1)若压强计的气密性很差,用手指不论轻压还是重压橡皮膜时,就会有漏气现象,因此U形管两边液柱的高度差变化小;调节好的压强计放在空气中时,橡皮膜不受液体的压强,因此U形管两边的液面应该相平.

(2)影响液体压强的因素有:液体的密度和浸入液体的深度,实验中没有控制金属盒浸入的深度相同,因此无法得出正确结论.

(3)液体密度相同时,压强与深度有关,金属盒离液面的距离越深,压强越大,U形管两边液柱的高度差就越大.

(4)同一深度,液体向各个方向的压强相等,因此金属盒距液面的距离相同时,只改变金属盒的方向,U形管两边液柱的高度差不变.

点评:这是一道综合实验题,此题的难点是液体压强计的有关知识,我们要了解压强计的原理,知道液体压强计的操作要求等.

阅读理解

Say you are a 17th century construction worker who’s worked long and hard to build a splendid tower for the dead wife of your emperor.

Now say that the emperor orders your fingertips cut off so you can never build another one. Yes, that is the Taj Mahal, one of the most famous buildings in the world. And the tale behind the construction is just as impressive(印象深刻的)as the building itself.

First, there’s the emperor of northern India, Shah Jehan, also called the King of the World. In 1612, Shah Jehan married Mumtaz Mahal. Madly in love, they had 14 children over the next 20 years. But then sadness came. As Mumtaz was about to give birth to child number 14, she said she had heard her unborn baby cry out. It was a sign of death. And as Mumtaz lay dying, she asked Jehan to build a lasting memorial(纪念物) to celebrate their love.

When the heartbroken Jehan appeared eight days after his wife’s death, his people were shocked to see that his coal-black hair had turned snow-white.

Putting away his sadness, Jehan ordered his wife’s dying wish carried out. More than 20,000 workers labored nearly 22 years to complete the construction. In 1653, Jehan placed Mumtaz’s remains in the center under the building.

And then, son number five, Aurangzeb, murdered his brothers and took over the power from his aging father. Hehan lived the rest of his days-eight years, to be exact - imprisoned not far from the Taj Mahal. Jehan was only allowed to climb onto the top of his prison to see the timeless treasure from a distance. But never again would he be allowed to visit it-until he was buried next to his wife.

Today 25,000 people visit the Taj Mahal each day. Though the reason for building the tower was a strange, sad story, those who see its breath-taking beauty are reminded of the happiness that inspired(激发……的灵感) its construction.

59.The first two paragraphs were written to show that _____.

A.the Taj Mahal is an unusual historic building

B. ancient Indian emperors were cruel

C. construction workers led a hard life in ancient India

D. India has some of the most famous buildings in the world

60.The Taj Mahal was first built as _____.

A. a prison          B. a gift to Mumtaz     

C. a memorial building        D. a tourist attraction

61.We learn from the text that Mumtaz probably died in _____.

A. 1626          B. 1632           C. 1634           D. 1653

62.The underlined word “happiness” in the last sentence refers to _____.

A. the married happiness of the emperor and his wife

B. the great pleasure Jehan once found in exercising his power

C. the happiness Jehan felt on completing the Taj Mahal

D. the pleasure tourists experience when visiting the Taj Mahal

单项选择题