题目

章老师在课堂做演示实验，把两枚儿乎相同的鸡蛋A和B，从同一高度由静止释放鸡蛋A直接落在地板砖上碎了；鸡蛋B装在有水的纸杯中随纸杯一起下落，落在地板上完好无损。对这一结果，下列说法正确的是（） A . 与地板接触前的瞬间，鸡蛋A的动量小于鸡蛋B的末动量 B . 与地板碰撞过程中，鸡蛋B的动量变化量小 C . 与地板碰撞过程中，鸡蛋B的动量变化慢 D . 与地板碰撞过程中，鸡蛋A的动量变化量小 In early spring, 1.. Cold air, bringing rain or even snow, easily tears up(破坏) the warmth of the spring within a night.However, with the coming of Guyu—the Grain Rain, the blue sky and gentle winds would finally stay. Falling usually on or around April 20 every year, Guyu is the sixth of the 24 solar terms(节气). 2..Sow(播种) grainsThis is an important period of the growth of grains. The ancient Chinese already knew that as Guyu comes, the weather will become warm enough for sowing. 3.Hope for safety and harvest4. , they will hold some ceremonies on Guyu, hoping for safety as well as harvest during the coming fishing season.Watch the peonyIt′s also a great time to see the peony, which is known as “the Queen of All Flowers” in Chinese culture. As a result, watching peonies becomes one of the most enjoyable activities for many. The flower is said to be the favourite of Empress Wu Zetian of the Tang Dynasty, who was the only woman ruler in Chinese history.Pick tea leavesTea leaves picked before Guyu are among the best tea leaves. 5.. So the habit of drinking tea at this time of year has become a tradition in some places of China.A. It is said that the tea leaves picked on the day of Guyu can drive away bad luckB. For those living near the seaC. The farmers usually catch the chance to plant rice, corn and beansD. the weather is becoming warmer and warmerE. It means the beginning of a lively summer and people get busy from now onF. It means the coming raining season last for a long time and people are free G. the changing temperature usually makes a number of Chinese people uncomfortable