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LoveT8
unless= if not ??? A body in motion remains in motion at a constant speed in a straight line unless acted upon by an external force. Q: unless= if not ??? What's the meaning of this sentence?
Jun 5, 2013 11:02 PM
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Answers · 7
'Conservation of linear momentum' If there is an external force, speed or direction can be changed, but otherwise not.
June 6, 2013
This is Newton's first law of motion. It means that an object that is moving will keep moving in the same direction at the same rate if something doesn't stop it. Imagine a ball rolling down a hill. If the ball doesn't hit something (a tree, for example) the ball will keep on rolling. This is in theory. In practice, the ball will be slowed down by friction. Imagine a ball being thrown in the air. In theory, the ball will keep flying in the same direction that it was thrown in unless it hits something. In practice, it will eventually fall because of gravity. This is a complicated answer, so please feel free to ask for clarification.
June 6, 2013
You got that right. unless = if not.
June 6, 2013
yes
June 5, 2013
LoveT8
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