题干

同学们做实验的装置如图所示,闭合开关,先将导体ab水平用力向右移动,导体cd也随之运动起来,则在以上的实验中下列说法正确的是(   )

A:实验装置中的甲装置产生的现象在生活中的应用是电动机

B:实验装置中的甲装置把电能转化为机械能

C:实验装置中的乙装置运用的原理是磁场对电流的作用

D:若将导体ab水平用力向左移动,导体cd的运动方向不变

上一题 下一题 0.0难度 选择题 更新时间:2015-09-11 01:18:32

答案(点此获取答案解析)

C

同类题5

阅读下面材料,从每题所给的A、B、C、D四个选项中选出最佳选项。

B

    Have you ever stayed in a hotel? Most Chinese hotels often provide guests with things like disposable (一次性的) toothbrushes, toothpaste, shampoo and slippers. Many guests like the idea because they don't have to bring their own. But, if you travel to Beijing, remember to bring your own things. Starting from June, some hotels in Beijing will no longer provide guests with these disposables. They want to ask people to use less disposable things.

    Many disposable things are made of plastic. People throw them away after only using them once. It is a waste of natural resources (资源) and is very bad for the environment. Do you know, one Chinese person makes as much as 400kg of waste a year! Most of that waste comes from disposable things. In Beijing, people throw away about 19,000 tons of plastic bags and 1,320 tons of plastic lunch bowls every year! Plastic can take between 100 and 400 years to break down. So the less plastic we throw out, the better. So, wherever you travel, bring your own things and use them again and again.

    Back at home and school, you can also do something to make our world a better place. Try to do these things in your daily life: Use cloth shopping bags, not plastic ones. After using a plastic bag, wash it out and let it dry. Then you can use it over and over again. Do not use paper cups. At your school canteen(食堂), use your own bowl and chopsticks instead of disposable ones.