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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
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
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
more than half that of the moon more than that of the moon more than twice that of the moon half that of the moon
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.
bring up take up build up pull up
one eighty one of eighty one the eightieth one eightieth
the attraction of the sun and the moon the sun, the moon and the wind the changing tide the factors affecting the tide
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