问题 问答题 简答题

简述固定磁场分路电阻的作用。

答案

参考答案:

为了避免脉动电流分量对电机换向的影响,在串励绕组旁并联一个固定分路电阻,使励磁绕组中流过的励磁电流的交流分量相应减小,从而改善电机换向。

阅读理解

Do you love holidays but hate the increase weight that follows? You are not alone.

Holidays are happy days with pleasure and delicious foods. Many people, however, are worried about the weight that comes along with these delicious foods.

With proper planning, though, it is possible to con­trol your weight. The idea is to enjoy the holidays but not to eat too much. You don’t have to turn away from the foods that you enjoy. The following suggestions may be of some help to you. 

Do not miss meals. Before you leave home for a feast (宴会), have a small, low-fat snack(小吃). This may help to keep you from getting too excited before de­licious foods.

Begin with clear soup and fruit or vegetables. A large glass of water before you eat may help you feel full. Use a small plate; a large plate will encourage you to have more than enough.

Better not have high-fat foods. Dishes that look oily or creamy have much fat in them.

Choose lean meat (瘦肉). Fill your plate with salad and green vegetables.

If you have a sweet tooth, try mints (薄荷) and fruits. They don’t have fat content as cream and chocolate.

Don’t let exercise take a break during the holidays. A 20-minute walk after a meal can help burn off excess (过多的) calories.

68. Holidays are happy days with pleasure but they may______.

A. bring weight problems

B. bring you much trouble in your life

C. make you worried about your foods

D. make you hate delicious foods

69. In order to really enjoy your holidays without putting on weight, you’d better ___.

A. drink much water and have vegetables only

B. not eat much food in high fat

C. not accept invitations to feasts

D. turn away from delicious foods

70. According to the passage, ___ is a necessary part to stop you from putting on weight.

A. vegetables           B. water         

C. calories of energy       D. physical exercise

71. Many people can’t help putting on weight after the holidays because they ___.

A. can’t control themselves          B. go to too many feasts

C. enjoy delicious foods             D. can’t help turning away from the foods

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