Newton's Third Law: True or False?

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UNknown 2010
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Hello,
True or False:
- According to Newton third law, the algebraic sum of the forces in the system is equal to zero.

I think the answer is FALSE because, the third law of Newton says that F1 = - F2

and the " - " is for the direction, so that F1 = F2 in the quantity ==> F1 + F2 [tex]\neq[/tex] 0
 
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Well, from what i understand from Newton's third law is, any force will have a counter force of the same magnitude in the opposite direction. So, if u add both, it would be zero.. however, i am not sure that is what they are asking..
 
The answer is true.
If F1 = - F2, the two forces are equal but one is negative
For example,
1+ -1 = 0
At least that is what I think
 
i think its false ,,,
because each force is acting on separate body,,
so we can not find the the algebraic sum of the forces ,,

 
UNknown 2010 said:
True or False:
- According to Newton third law, the algebraic sum of the forces in the system is equal to zero.
This question is impossible to answer without further information on what "the system" means. We have a template that specifically asks for

Homework Statement

. You should have followed the template, UNknown.

redrose_emf said:
i think its false ,,,
because each force is acting on separate body,,
so we can not find the the algebraic sum of the forces
Sure you can. Just add them vectorially. This is a very important concept. The (vectorial) sum of all internal forces must be zero in an isolated system.
 
D H said:
Sure you can. Just add them vectorially. This is a very important concept. The (vectorial) sum of all internal forces must be zero in an isolated system.

thank you for the correction ,,,