Question

　　 The full of gravity of the sun, which is less half than that of the moon, somewhat makes matters difficult or complex. When there is a new moon, the moon is placed between the earth and the sun so the attraction of the sun and the moon strengthens each other. Two weeks later, when the moon is full, it has moved round to the opposite side of the earth to the sun so that the earth is between them and once again they are pulling on the ocean, this time in opposite directions but along the same axis (轴线). At these times the earth experiences its highest tides (潮汐), commonly known as spring tides.

1. Which of the following statements is true?

A．The pull of gravity of the sun is greater than that of the moon

B．If the pull of gravity of the Sun is 10, then the pull of gravity of the moon is 20

C．The pull of gravity of the moon, sometimes has great effect on the earth

D．When there is a new moon, the earth experiences its highest tides

2. According to the passage, tell which is the new moon from A,B,C,D in the picture.

 

 

Answer 1

答案：CA
提示：

1.　　   月球对地球的引力是太阳对地球引力的两倍多,AB都错; 潮汐现象是在满月的时候When the moon is fool, D错 2.　　   新月的时候月球在太阳和地球的中间When there is a new moon, the moon is placed between the earth and the sun