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- 精华
- 3
- 积分
- 1423
- 经验
- 1423 点
- 威望
- 119 点
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- 554 ￥
- 魅力
- 354
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1.2.3 测Mount Everest 的高度
测珠峰（Mount Everest）高度（两段）:
P1 ：某年，中国重新测了珠峰，用的是传统的目测法(Visibal….).
评价此方法（负）是目测什么海拔仪，但是目测时是透过光线的折射读数，（大概是像温度计一样读数的）因为空气状况会随温度和压力变化，此读数不精确。
解决缺点：为了减小误差，测量队尽量来到离峰顶只有几迈到十几迈的地方。（考题5）
P2 ：测量中在三点上改进了此传统方法。第一，。。。；第二，。。。；第三，用红旗子标记了以前测量点，下次确定还在这点测量（很好懂，第一段有关于仪器的描述有点晕，但是不需要看懂）
GWD-26-Q32-Q35 中国人改进了英国人测量珠峰高度的方法
In 1975 Chinese survey teams 1975年中国人量度珠峰，使用的
remeasured Mount Everest, the highest 技术和1852年英国人的相同。
of the Himalayan mountains. Like the 他们从海岸线开始行进，每隔几
Line British in 1852, they used the age-old 步量度一次上升高度。
(5) technique of “carrying in” sea level:
surveyors marched inland from the
coast for thousands of miles, stopping
at increments of as little as a few feet
to measure their elevation, and mark-
(10) ing each increment with two poles.
To measure the difference in elevation 使用工具：置于两根杆中间的望
between poles, surveyors used an 远镜。
optical level—a telescope on a level
base—placed halfway between the
(15) poles. They sighted each pole, read-
ing off measurements that were then
used to calculate the change in eleva-
tion over each increment. In sight of 看到峰顶时，他们使用经纬仪
the peaks they used theodolites— 探定顶点的上升。
(20) telescopes for measuring vertical and
horizontal angles—to determine the
elevation of the summit.
The Chinese, however, made 但中国人努力改正英国人的误
efforts to correct for the errors that 差。
(25) had plagued the British. One source 误差1：由于不同温度压力造成
of error is refraction, the bending of 的光折射。这会产生峰顶幻象。
light beams as they pass through air
layers of different temperature and
pressure. Because light traveling.
(30) down from a summit passes through
many such layers, a surveyor could
sight a mirage rather than the peak
itself. To reduce refraction errors, the 解决：1，减少通过经纬仪的光，
Chinese team carried in sea level to 2，使用天气气球测量温度压力。
(35) within five to twelve miles of Everest’s
summit, decreasing the amount of air
that light passed through on its way to
their theodolites. The Chinese also
launched weather balloons near their
(40) theodolites to measure atmospheric
temperature and pressure changes
to better estimate refraction errors.
Another hurdle is the peak’s shape. 误差2：测量者们的测量点不同。
When surveyors sight the summit.
(45) there is a risk they might not all
measure the same point. In 1975
the Chinese installed the first survey 解决：安装一个红色灯塔。
beacon on Everest, a red reflector
visible through a theodolite for ten
(50) miles, as a reference point. One 误差3：海平面不平。
more source of error is the uneven-
ness of sea level. The British
assumed that carrying in sea level
would extend an imaginary line from
(55) the shore along Earth’s curve to a
point beneath the Himalaya. In
reality, sea level varies according
to the irregular interior of the planet.
The Chinese used a gravity meter to 解决：用重力计改正误差。
correct for local deviations in sea level.
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Q32
It can be inferred from the passage that
refraction would be most likely to cause
errors in measurements of a mountain’s
elevation under which of the following
conditions?
A. When there are local variations in sea
level
B. When light passes through humid air
C. When theodolites are used relatively far
from the mountain peak.
D. When weather balloons indicate low air
temperature and pressure.
E. When sea level has been carried in to
Within five to twelve miles of the summit.
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Q33
Which of the following best describes the
purpose of the sentence in lines 23-25
(“The Chinese…the British”)?
A. Introduce a definition
B. Signal a transition in focus
C. Summarize the preceding paragraph
D. Draw a contrast between two different
theories.
E. Present information that contradicts the
Preceding paragraph.
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Q34
Which of the following is NOT mentioned as a
possible source of error in surveying mountain
elevation?
A. Mirages （幻景）
B. Refraction（折射度）
C. Inaccurate instruments
D. Variations in sea level （海平面不平）
E. Uncertainty about the exact point to be
Measured
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Q35
The primary purpose of the passage is to
A. provide details about improvements to a
process
B. challenge the assumptions underlying a
new method
C. criticize the way in which a failed project
was carried out
D. call for new methods to solve an existing
problem
E. explain the theory behind a new technique
5.为了减小误差，测量队尽量来到离峰顶只有几迈到十几迈的地方。此处有题：
答：答案就是离峰顶更近。 |
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