This acceleration is due to a force called Gravity .it is this force which holds
us on the groundand holds the moon moving around the earth .No one knows how
Gravity works,but it is a force of attraction that pulls matter together.Every bit of matter
in the universe, from an atom to a star, exerts its own gravitational pull on other matter.Big objects exert more pull than small objects -
更新1:
which is why we feel the pull of the earth's gravity, but not that of, say, a brick. 1. What is gravity? 2. Does the moon have gravitational pull? 3. Why can't we feel the pull of a brick? 4.why can't we feel the pull of a brick?
更新2:
which is why we feel the pull of the earth’s gravity,but not that of, say, a brick. 1. What is gravity? 2. Does the moon have gravitational pull? 3. Why cannot we feel the pull of a brick? 4.what makes on object fall faster and faster towards the ground
更新3:
http://hk.knowledge.yahoo.com/question/?qid=7007082104060
