问题 选择题

由磁感应强度的定义式B=F/IL可知(  )

A.若某处的磁感应强度不为零,则通电导线放在该处一定受安培力

B.通电导线放在磁场中某处不受安培力的作用时,则该处的磁感应强度一定为零

C.同一条通电导线放在磁场中某处所受的磁场力是一定的

D.磁场中某点的磁感应强度与该点是否放通电导线无关

答案

A、当通电导线与磁场平行时,B不为零,但导线不受安培力.故A错误.

B、通电导线放在磁场中某处不受安培力的作用时,可能是由于通电导线与磁场平行,B并不为零.故B错误.

C、同一条通电导线放在磁场中某处所受的磁场力不一定相同,与电流和导线受到放置的角度均有关.故C错误;

D、磁感应强度的定义式B=

F
IL
采用比值定义法,可知磁感应强度与该点是否放通电导线无关,由磁场本身的特性决定.故D正确.

故选D

阅读理解

Summer Cultural Exploration in France

The Summer Cultural Exploration program in Amboise, France, provides students with the opportunity to study French in a friendly historic atmosphere while experiencing a taste of French culture.

Amboise

Amboise is a charming small town on the Loire River in central France. The royal Amboise castle was the preferred residence of Charles VIII, who built it in the 15th century. With a rich history and beautiful natural scenes, Amboise is the ideal environment for students to study French.

Learn

French courses take place every morning, Monday through Friday, for four hours per day in a historic 19th-century building in the center of Amboise. Students will be given an exam upon arrival to make sure that they attend a language class of the appropriate level. An interactive teaching approach is stressed.

Experience

There is a good balance between planned activities and free time throughout the four-week program. Two to three days per week, organized activities are offered such as: lecture on topics in French history, literature, art and cinema, showing of French films, and a visit to Leonardo da Vinci’s home at the Clos Luce.

Travel

Also, students will explore France through the following guided trips.

●Chambord, Cheverny and Blois —Explore two of the area’s famous castles. Chambord, the largest of the Loire castle, was built by the great Renaissance king, France I. Chevernby castle was built in 1630. Visit the old town of Blois, a favorite residence of French royalty.

●Villandry and Sache — One of the last Renaissance castles to be built along the Loire, Villandry, is also known for its flower and vegetable gardens. The lovely old castle of Sache was a best-loved house of the great 19th-century writer Honore de Balzac.

●Paris — Discover the City of Light, famous for its fashion, food and art during a journey to Paris! Walk along the banks of the Seine River, visit Notre Dame Cathedral and discover some of the city’s famous museums and including the Louvre.

Housing

Students stay with carefully-selected host families. Ability to remain open-minded and tolerance of cultural differences are required. There is an 11 pm curfew(熄灯时间)for this program.

小题1:When a student gets to Amboise, he or she will first _______.

A.take a language test

B.visit da Vinci’s home

C.hear lectures on French history

D.go to see the castle built by Charles VIII小题2:Students can enjoy beautiful flowers at _______.

A.Chambord castle

B.Cheverny castle

C.Villandry castle

D.Sache castle小题3:Students who want to take part in the program will _______.

A.mainly study cultural differences

B.spend most of their time in Paris

C.live in a historic building

D.study for 20 hours a week小题4:What is the purpose of the text?

A.To advertise.

B.To educate.

C.To entertain.

D.To instruct.

判断题