sticks点拨:由some可知用名词的复数形式. 查看更多

 

题目列表(包括答案和解析)

在物理学中,磁场的强弱用磁感应强度(用字母B表示,国际单位是特斯拉,符号是T)来表示,磁感线越密的地方,磁场越强,磁感应强度B越大.

(1)在图20中,甲为某磁极附近磁感线的方向和分布的示意图,由图可知,该磁极为 ▲ 极,若在l处放置一个小磁针,当小磁针静止时,其指向应是图乙中的  ▲   .
(2)磁敏电阻阻值的大小随磁场的强弱变化而变,图丁是某磁敏电阻R的阻值随磁感应强度B变化的图象,据图线可知,磁敏电阻的阻值随磁感应强度B的增大而▲ .图线没有过坐标原点,说明  ▲  .
(3)王强设计了一个可以测量该磁敏电阻R的电路如图丙所示,(其中磁敏电阻所处的磁场未画出).将该磁敏电阻R放置在磁场中的位置某处,测出电阻后,利用R—B特性曲线可以读出相应的磁感应强度.
①在图甲磁场中1处,测得的数据如图20表中所示,则该磁敏电阻的测量值为 ▲ Ω. 
②根据该磁敏电阻的R-B特性曲线可知,1处的磁感应强度为   ▲    T.
③在实验过程中,仅将磁敏电阻从1处移至2处,其它条件不变,那么电流表的示数
▲   (填“增大”、“减小”或“不变”).
④依据上述方法获得的磁感应强度B的测量值与该点实际值存在不小的误差,为尽可能准确反映空间某点磁场的强弱,你认为在选择磁敏电阻时应注意什么问题?

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用括号内名词的适当形式填空:

Put some more ______ (wood) on the fire.

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用所给名词的适当形式填空

Would you like to have some ________(tea)?

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完形填空

阅读下面短文,掌握其大意,然后从各题所给的A、B、C和D四个选项中选出最佳选项。

  Canada is the second largest country in the world.It is over 7 000 kilometers from the   1   coast(海岸)to the east.It   2   six time zones.  3   it is 9 a.m.in Vancouver on the west coast, it is 1.30 p.m.in St John's on the east coast.

  English and French   4   the two main languages in Canada.About 60 percent of   5   people speak English, and about 25 percent speak French.More   6   70 percent of its population live in cities near the US border(边境).

  Ottawa is the capital.Every year millions of tourists go there to   7   museums and take part in the cultural(文化的)activities.Toronto is the largest city of the country   8   about 2.5 million people.Montreal is   9   second biggest French-speaking city in the world.

  The maple leaf is the national symbol of Canada.The Canadian flag has a red maple leaf on a red   10   white background.

由本文可知:加拿大是世界上第二大国,海岸线长7000多千米,有6个时区,主要讲英语和法语,渥太华是首都,多伦多是最大的城市,枫叶是加拿大的标志。考点涉及到名词、动词、副词、介词、冠词、连词等用法及对文章的整体理解能力。

(1)

[  ]

A.

west

B.

east

C.

south

D.

north

(2)

[  ]

A.

is

B.

had

C.

has

D.

have

(3)

[  ]

A.

Which

B.

What

C.

Where

D.

When

(4)

[  ]

A.

are

B.

is

C.

will be

D.

has been

(5)

[  ]

A.

their

B.

his

C.

its

D.

our

(6)

[  ]

A.

up

B.

over

C.

about

D.

than

(7)

[  ]

A.

see

B.

visit

C.

look

D.

find

(8)

[  ]

A.

with

B.

for

C.

from

D.

at

(9)

[  ]

A.

a

B.

an

C.

the

D.

/

(10)

[  ]

A.

or

B.

and

C.

but

D.

however

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