问题 问答题

(B组)发射神舟五号飞船的火箭(连同上端的飞船)总高度为58m,发射塔高度为70m.一人在观看电视直播报道时,在头脑中记下火箭上端的位置A(如图),用自己的手表测出火箭从开始发射到下端通过A点用的时间约为8s.假设火箭开始阶段是匀加速直线运动,请你根据上述已知条件,求出火箭在开始运动阶段的两个运动学物理量.

答案

根据匀加速运动的位移公式s=

1
2
at2

a=

2s
t2
=
2×58
82
m/s2=1.81m/s2

根据匀变速运动的平均速度公式

.
v
=
v0+v
2
=
0+v
2

v=2

.
v
=2×
58
8
m/s=14.5m/s

答:可以求出火箭的加速度a=1.81m/s2

以及火箭的末端通过A处的速度v=14.5m/s.

单项选择题

Passage Three

Uffizi Tries to Outdo Louvre
Uffizi试图胜过卢浮宫
Italy is to try to turn the Uffizi gallery in Florence into Europe’s premier art museum, with an ambitious 56m euro scheme to double its exhibition space.
Giuliano Urbani, Italy’s culture minister, said the enlarged gallery would surpass "even the Louvre".
By the time work is completed, visitors to the extensively remodeled Uffizi will be able to see 800 new works, including many now confined to the gallery’s storerooms for lack of space.
The project—the outcome of nine months of intensive work by a team of architects, engineers and technicians—is a centrepiece of the cultural policy of Silvio Berlusconi’s government.
With refurbishment plans also afoot for the Accademia in Venice and the Brera in Milan, Italy is bent on securing its share of a market for cultural tourism that is threatened not just by the Louvre, but also by the " art triangle" of Madrid, which takes in the Prado, the Thyssen collection and the Reina Sofia museum of art.
Schemes for the expansion of the Uffizi’s exhibition space stretch back almost 60 years. The latest was mooted in the mid-1990s.
But the one adopted by the present Italian government has reached a far more advanced stage than any of its forerunners. Roberto Cecchi, the government official in charge of the project, said yesterday that all that remained to do was to tender for contracts.
The first changes will be seen as early as next week when a collection of pictures by Caravaggio and his school, including the artist’s Bacchus, currently crammed into a tiny room on the second floor, is to be moved to more expansive premises on the first.
Mr.Cecchi said the biggest problem faced by his team was "inserting a museum into a building that is itself a monument". The horseshoe-shaped Palazzo degli Uffizi, began in 1560, was designed by the artist and historian Giorgio Vasari.
The latest plans are bound to stir controversy, involving as they do the creation of new stairwells and lifts in the heart of the building. There has already been an outcry over one proposed element, a seven-storey, canopy-like structure for a new exit by the Japanese architect Arata lsozaki.
But Mr.Urbani said in Florence on Tuesday that part of the scheme was "subject to further evaluation".
At the heart of the plan is the opening up of the first floor of the vast building, which for decades was occupied by the local branch of the national archives.
This will allow visitors to follow a more extensive, and ordered, itinerary that would turn the Uffizi into what Antonio Paolucci, Tuscany’s top art official, called "a textbook of art history".
As at present, visitors will be channelled to the second floor, where they will be able to study early works by Cimabue and Giotto before moving on to admire the gallery’s extraordinary collection of Renaissance masterpieces, including Botticelli’s Primavera.
But most of what was painted after 1500 is to be moved down a storey to new exhibition space, and on the ground floor there will be a more extensive collection than at present of modern art. The overall increase in exhibition space will be from 6,000sq metres to almost 13,000.
Asked if the expansion might not increase the risk of inducing Stendhal’s syndrome—the disorientation, noted by the French novelist, in those who encounter dozens of Italian Renaissance masterpieces—Mr. Cecchi replied fatalistically, "Yes. It’ll double it".

Which of the following is true of Uffizi

A.It is threatened by the Louvre and the "art triangle" of Madrid.

B.It is going to be remodeled by transforming its storerooms into showrooms.

C.It involves a maintenance fee of 56m euro.

D.It is a major attraction for Italy’s cultural tourism.

单项选择题