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different weight systems in different places freedom from traditional ideas traveling from the earth to the moon the effect of gravitation on weight
about 384 000 kilometers 240 000 kilometers only 348 000 kilometers about 384 000 meters
different weight systems in different places. freedom from traditional ideas. traveling from the earth to the moon. the effect of gravitation on weight.
it is too small to have a gravitational pull of its own its pull is so small that we tend to ignore it its pull disappears in the presence of the earth’s gravitation it tends to melt and loses its gravitational pull
about 384 000 kilometers 240 000 kilometers only 348 000 kilometers about 384 000 meters
nothing many things everything little
it demands too great an effort for us to do so we are too familiar with the way things are to question the ideas we have proved that those ideas are correct we are so sure of ourselves that we never doubt anything on the earth
it is fixed if it is outside the earth’s gravitational pull it decreases four times when it is 4,000 miles from the earth’s center it varies with the change of the gravitational attraction between two objects things increase in amount as they are closer to the earth’s surface
1 pound. 2 pounds. 3 pounds. 4 pounds.
the sun the moon all the stars some planets
the moon is 240 kilometer far away we don't know where it is it can't fly without air there is no air on the moon
when the moon is new or full when the moon and sun have declination of the same name only when the moon and sun are on the same sides of the earth at the beginning of spring when the sun is over the equator"
nothing many things everything little
the moon is 240 kilometer far away we don't know where it is it can't fly without air there is no air on the moon
at the start of spring，when the Sun is nearly over the equator only when the Sun and Moon are on the same sides of the Earth and are nearly in line when the Sun and Moon are at approximately 90 °to each other， as seen from the Earth when the Sun，Moon，and Earth are nearly in line ，regardless of alignment order"
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