题干

在如图所示的四个电路中,电源电压相同且不变,电阻R的阻值均相等,闭合电键S,电流表示数不变的是(   )

A:

B:

C:

D:

上一题 下一题 0.0难度 选择题 更新时间:2018-01-21 03:01:56

答案(点此获取答案解析)

D

同类题5

阅读理解

    The latest study by the University of Florida has found that eating from smaller, less beautiful, and even paper plates will help prevent overeating. Eating with a fork instead of a spoon can help you lose weight, the researchers say. Much to their surprise, they find that putting mirrors in the dining room will also help reduce weight.

    The researchers asked 185 college students to choose a chocolate cake or a fruit salad, and evaluated the taste. Those who ate in a room with a mirror scored the taste of junk food much lower than those in a room without a mirror. But the taste of fruit salad remained the same in any case.

    Lead scientist, Dr. Ata Jami, says that a glance in the mirror tells people more than just about their physical appearance. It enables them to view themselves objectively (客观地) and helps them to judge themselves and their behavior in the same way that they judge other people.

    The mirrors were found to push people to compare and match their own behavior with accepted social standards. The researchers believe it proves that people don't want to look in the mirror when they feel they are following the social standards. When they look in the mirror with mouths full of junk food, feelings of discomfort and failure can be increased. Therefore, the presence of the mirror lowers the taste of unhealthy food.

    However, researchers say this is only the case if people select the food they are eating, because they are responsible for that choice. The researchers suggest that mirrors be placed in dining rooms and other eating spaces, so that people will start eating more healthily.