问题 填空题

图甲是用水来冷却牛奶的示意图。图乙是记录牛奶、水的温度随时间变化的图像,图乙中表示热牛奶温度随时间变化的曲线应是       (填“1”或“2”)。若水的质量为1.5kg,在达到A点表示的温度的过程中,水          (填“吸收”或“放出”)的热量是          

答案

1  吸收  6.3×104J

分析:(1)图象可以告诉我们很多知识,用水来冷却牛奶,热牛奶的温度是逐渐降低的,所以温度随时间降低的是热牛奶的温度随时间图象.

(2)看图可以发现最后水和牛奶的温度将趋于一致,这个温度是它们进行热传递后的温度即末温,在这个过程中水吸收的热量可以根据Q=cm(t-t0)求出.

解答:解:(1)用水来冷却牛奶,热牛奶的温度是逐渐降低的,所以热牛奶温度随时间变化的曲线应是1;

(2)A点温度即20℃,它是水和牛奶热传递后的温度即末温.

这个过程中水吸收的热量:

Q=cm(t-t0)=4.2×103J/(kg?℃)×1.5kg×(20℃-10℃)=6.3×104J.

故答案为:1;吸收;6.3×104J.

阅读理解

Wen Jiabao arrived in Singapore yesterday for an official visit to the country. It is the first visit by a Chinese premier to Singapore in eight years. In the arrival statement, When said he is looking forward to the meeting with Singing pore on ways to deepen East Asian cooperation between two nations so as to contribute to the building of a peaceful, harmonious relationship.
Premier Wen Jiabao and Singapore Prime Minister Lee Hsien Loong agreed to jointly develop an environmentally friendly city in northeastern China. The city will be a model for sustainable development, a Singapore government statement said.The”Sino-Singapore Tjanjin Eco—city” will be developed by a joint venture formed by Chinese and Singapore companies.”This eco-city, to be built in Tianjin, well become another highlight in our relations,” When said after signing an agreement with Lee, who agreed,“On the Singapore side, on all levels,we’ll  give this project our full support.”
The two sides will share expertise and experiences in urban planning, environmental protection, resources conservation,recyeling,use of renewable resources and wastewater re-use. China’s  economil planning agency issued a set of guidelines earlier this month welcoming foreign investment in environmentally friendly areas such as recycling,”clean”industries and environmental protection.
Bilateral relations between China and Singapore have seen big progress even though the two countries established diplomatic ties only 17 years ago, When said during his talks with Lee.
China and Singapore have also kept close contact and coordination on regional issues, he added. When said China and Singapore are both important Asian countries that share common interests in many areas.
Title: Wen’s visit to Singapore
Main points
contexts
General   小题1:   of Wen’visit
To   小题2:   with Singapore
To   小题3:  
Agreements 小题4:  in the visit
Another 小题5: friendly city to be built in Tianjin.
Co-operation in city planning, environment protection, recycling and so on for  小题6: 
Co-operation in   小题7:  for a  小题8:  Asia.
Guidelines 小题9: by China
China’s  小题10:  for clean industries and environmental protection.
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