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If you treble the distance, the gravitational attraction gets nine times weaker.如將距離增大兩倍, 則其萬有引力就減小九分之八.Many asteroids are weakly bound piles of rubble, held together by their own minute gravitational attraction.大多數(shù)的小行星都...

gravitational attraction的音標(biāo)：...

地球[萬有]引力...