Is Momentum Conserved with Different Force Directions and Types?

AI Thread Summary
Momentum is conserved in the absence of external forces in a specific direction, meaning that if no external forces act in the x direction, the y component of momentum remains constant. Work done by conservative forces does not necessarily imply that momentum is conserved, as external forces can still affect momentum. The Work-Kinetic Energy theorem holds true only when work is done by conservative forces; otherwise, it becomes invalid. Providing reasoning for answers can enhance understanding and clarity in discussions. Engaging with the principles of momentum and work is crucial for grasping these concepts effectively.
dherm56
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5) If there are no external forces acting on a system in the x direction, but there is an external force acting on the system in the y direction, then the y component of momentum of the system is constant.

True
False

6) If work is done on an object by only conservative forces, then the momentum of that object must be conserved.

True
False

7) The Work-Kinetic Energy theorem is invalid if work is done by a non-conservative force.

True
False

I answered False, True, True.
any sugestions?
 
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How about showing one's reasoning.
 

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