题干

小明的妈妈为了改善早餐的营养,买了一台全自动豆浆机,如图甲所示。图乙所示是豆浆机的主要结构:中间部位是一个带动刀头的电动机,用来将原料进行粉碎打浆;外部是一个金属圆环形状的电热管,负责对液体加热煮沸。下表是这个豆浆机的主要技术参数;图丙所示是豆浆机正常工作做一次豆浆的过程中电热管和电动机交替工作的“Pt”图像。

请解答下列问题:

①豆浆机正常工作时的最大电流是多大?

②豆浆机正常工作做一次豆浆,总共消耗的电能是多少?

③在一次豆浆机工作的时候,小明将家里的其它用电器都关闭,他观察到豆浆机的电热管工作时,家里标有“2400r/kW·h”字样的电能表转盘在2min内转过了80转。此时电路的实际电压是多大?

上一题 下一题 0.0难度 选择题 更新时间:2018-05-04 02:02:08

答案(点此获取答案解析)

解:①已知最大功率P1=1210W,所以正常工作时的最大电流: I1=P1U=1210W

同类题2

根据短文内容,从短文后的选项中选出能填入空白处的最佳选项,其中有一项为多余选项。

    Growing up is not always easy. When we face difficulties, we should never give up. We should try our best to make the life better. It is not useful to cry for help. Hong Zhanhui's story of growing from boy to man tells us about this.

    Hong was born in 1982 in a poor family in Henan Province. When he was only 11, his father became badly ill. And one day he came back with a baby girl. The girl was very young and they must spend much time looking after her. However, a year later, Hong's mother left home.____ So everything fell onto the young boy:to take care of his father and the sister, and to go on to study.

    Although his life was very hard, Hong didn't go away from his father and sister.____. He climbed tall trees to get birds' eggs for his sister. He walked two hours at weekends to the market to buy different things. Then he sold the things around his school to make some money.

    ____. To take care of his sister, he worked hard to rent(租) a room near his college for her, and sent her to school every day.

    When people knew Hong's story, he became a hero in people's eyes. Many people wanted to help him. But Hong refused the help from others. He said he felt happy by other's help, but he believed he could take care of his family by himself.____.

A. He worked in a part-time job to look after his family.

B. His life was hard, but he has grown up from boy to man.

C. A few years later, he began to study at a college.

D. She no longer wanted to live such a poor life and face her sick husband.

E. Because of the hard life, he felt sad and wanted to give up.