题干

如图所示,一光滑水平桌面的左半部分处于竖直向下的匀强磁场内,当一电阻不计的环形导线圈在此水平桌面上向右以某一速度开始滑行时(   )

A:若整个线圈在磁场内,线圈一定做匀速运动

B:线圈从磁场内滑到磁场外过程,必做减速运动

C:线圈从磁场内滑到磁场外过程,必做加速运动

D:线圈从磁场内滑到磁场外过程,必定放热

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答案(点此获取答案解析)

A,B,D

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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。选项中有两项为多余选项。

    The key to losing weight is to understand what really interests you. Have you ever been excited about losing a few pounds? ____ And to help you keep your weight under control, you need some coping strategies (策略).

Ask questions. When you're researching different dieting products and plans or even talking to a doctor about diets, ask as many questions as you can. ____ Ask questions like: Do I have to buy special meals? Does the program include a part to help me keep my weight loss?

    Get real. ____ Don't burden yourself with unrealistic expectations. Remember, large amounts of weight loss are not realistic and are most likely not safe or healthy. Talk with your health care professional to determine a healthy weight goal.

    ____ To keep your weight, you must balance your intake of calories with the energy you burn. Just 30 minutes of fast walking in most days can take about 10 pounds off your weight each year.

    Weigh yourself weekly. It's important to track your weight on any diet or weight loss plan, but don't get on the scale every day. Weighing daily won't show you the big picture. ____

A. Stay balanced.

B. Once a week is fine.

C. Stick with your healthy eating plan.

D. Losing one to two pounds a week is a realistic goal.

E. Being well informed will help you choose the best diet for you.

F. Regular weight check-ins will show you your progress over time.

G. If so, you must find a way to turn that excitement into determination.