Can Motion Exist Without Force?

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True or false :

It is possible to have motion in the absence of a force (F)
beacuse no motion without force

If an object is not moving , no external force acts on it (T)
beacuse each object will not move unless a force acts on it

If a single force acts on an object , the object accelerates ( T)
beacuse every object has force has accelerates

If an object experiences an acceleration , a force acts on it ( T)
beacuse every object has force has accelerates


If an object experences no acceleration , no external force acts on it ( T)
beacuse every object has no force has no accelerates

If the net force acting on an object is in the x direction the object moves in the x direction ( T )
beacuse when force effet on the object will go same direction of force

I want check my answer please >>


The Attempt at a Solution

 
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By my count you have 2/6 correct, 4/6 wrong. Think about the difference between velocity and acceleration.
 
It would be much easier to help if you explained your reasoning.
 
I explained my reasoning by apply Newton second law
 
r-soy said:
I explained my reasoning by apply Newton second law

Why don't you explain what you think motion means? The term appears in a number of problems that you got wrong, so you might want to be more specific about things.
 
I get the similar count as phyzguy. Try explaning the reasoning to each prob .. exactly why you chose whether true or false.
 
r-soy said:
?
Do you not know what "explain" and "reason" mean?
 
r-soy said:
True or false :
I can't imagine how you would answer these "true" or "false". Many of them simply don't make sense.

It is possible to have motion in the absence of a force (F)
beacuse no motion without force
The 'because' seems to contradict the statement!

If an object is not moving , no external force acts on it (T)
beacuse each object will not move unless a force acts on it
Again, a non-sequitur. "because each object will not move unless a force acts on it" would explain "if an object is moving there must be an external force acting on it", not the statement given.

If a single force acts on an object , the object accelerates ( T)
beacuse every object has force has accelerates
Okay- not very good English, but true.

If an object experiences an acceleration , a force acts on it ( T)
beacuse every object has force has accelerates
Once again a "p implies q because q implies p" statement. Not logical.


If an object experences no acceleration , no external force acts on it ( T)
beacuse every object has no force has no accelerates
The statement is true but because of "every object that has a force accelerates" not the reason given here.

[qote]If the net force acting on an object is in the x direction the object moves in the x direction ( T )
beacuse when force effet on the object will go same direction of force [/quote]
True

I want check my answer please >>


The Attempt at a Solution

Most of these seem to be of the form "if p then q because if q then p" (which is false logic). Also, as others have tried to point out, an object can move in a straight line, at constant speed, with NO force on it. You don't seem to realize that.
 
but all my answer are correct ??
 
HallsofIvy said:
Most of these seem to be of the form "if p then q because if q then p" (which is false logic). Also, as others have tried to point out, an object can move in a straight line, at constant speed, with NO force on it. You don't seem to realize that.

Halls, I assumed that the "because ..." following each question was his/her attempt at justifying the answer (T/F) that he/she gave for the statement above that line. If that's the case, then the questions make sense, it's just that the OP's explanations don't.
 
r-soy said:
but all my answer are correct ??

Most of your answer are not correct if you've correctly transcribed each statement.