题干

为判断短跑比赛是否抢跑,某兴趣小组设计了如图“抢跑自动指示”电路。其工作原理是:当运动员蹲在起跑器上后,先闭合S;发令时闭合S1,发令指示灯亮;运动员起跑后,装在起跑器上的压敏电阻R0因受到压力减小,其电阻改变,电磁铁线圈中的电流明显变大,S2被吸引而闭合,起跑器指示灯亮。

上一题 下一题 0.0难度 选择题 更新时间:2016-10-24 06:16:02

答案(点此获取答案解析)

同类题3

    When someone has deeply hurt you, it can be very difficult to let go of your anger. But forgiveness is possible - and it can be surprisingly helpful to your physical and mental health. Indeed, research has shown that people who forgive have more energy, better appetite (胃口) and better sleep. “People who forgive show less anger and more hopefulness,” says Dr. Frederic Luskin, who wrote the book Forgive for Good. “So it can help save on the wear and tear(消耗) on our body and make people feel more energetic.”
    So when someone has hurt you, calm down first. Take plenty of breathe deeply and think of something that gives you pleasure: a beautiful scene in nature, someone you love. Don't wait for an apology(道歉). “Many times the person who hurt you may never think of apologizing,” says Dr. Luskin. “They may have wanted to hurt you or they just don't see things the same way. So if you wait for people to apologize, you could be waiting a very long time.”Keep in mind that forgiveness does not necessarily mean accepting the action of the person who makes you angry. Mentally going over your hurt gives power to the person who brought you pain. Instead, learn to look for the love, beauty and kindness around you. Finally, try to see things from the other person's perspective(视角). You may realize that he or she was acting out of ignorance (无知), fear, even love. To achieve the perspective, you may write a letter to yourself from that person's point of view.