题干

一个物体受到两个力的作用,如果两个力的三要素完全相同,那么这两个力是(   )

A:一对相互作用力

B:同一个力

C:可以互相抵消的两个力

D:大小、方向、作用点都相同的两个力

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答案(点此获取答案解析)

D

同类题3

阅读表达。阅读下面短文并回答问题,然后将答案写在试卷相应的位置(请注意每题的词数要求)。

【1】A safari park is a park in which wild animals are kept. They are mainly located in east or central Africa. They often occupy a very wild area, with mountains and rivers. To visit the park and look at the animals, people have to drive around in a car for a few of hours because the park is huge.

【2】In south Africa there is a safari park, which contains all sorts of wild animals like lions, elephants, rhinoceroses(犀牛), zebras, wild pigs, deer and giraffes.

【3】There is a wild road leading through the park, but nobody is permitted to walk on the road. Anyone traveling in the park has to go in a car because wild animals may fiercely attack people. From the car he may see almost every types of African wildlife. Some of these are getting scarce (稀有的) because people kill them for various reasons. For example, rhinoceroses are killed for their horns (角), which are used in traditional Chinese medicines for colds and headaches. Perhaps they will be seen only in museums and books one day.

【4】Travels may buy food for the animals. They can feed them when they tour the park. Of course, they should not feed them in a close distance because the wild animals may attack people. In addition, they should only give proper food to the animals.

【5】A traveler may carry a gun with him in his journey. The gun is given to him by the government. However, it is not used for hunting. In fact, a seal(封条) is fixed to it. The traveler may fire at a wild beast to defend himself in case he is attacked. However, he has to prove to the government that he has been attacked and that he has not fired at a harmless animal.