How Do Forces Affect Acceleration on a Frictionless Surface?

AI Thread Summary
In a discussion about the forces acting on a 20 kg box on a frictionless surface, participants clarify the application of Newton's law, specifically force equals mass times acceleration. When the box accelerates at 11 m/s², the net force calculated is 220 N. However, when the box accelerates at 1 m/s² in opposite directions, a different equation is needed to determine the individual forces. The correct magnitudes of the forces are identified as 120 N and 100 N. Understanding the relationship between net force and individual forces is crucial for solving such problems.
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a 20 kg box is on frictionless surface acted on by two horizontal surfaces. when in same direction, it pulls 11 m/s but in opposite directions, it pulls only 1 m/s. determine magnitude of each force.
answer: 120 N , 100 N

okay...i need help with this. i am using Newtons law: force=mass x accelleration
i am trying to find force. mass is 20 kg and accelleration is 11 m/s. when i plug in that number, i get 220N. can someone please help?
 
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beocom6000yello said:
a 20 kg box is on frictionless surface acted on by two horizontal surfacesyou mean forces[/color]. when in same direction, it pullsyou mean accelerates[/color] 11 m/sm/s^2 [/color]but in opposite directions, it pulls only 1 m/s accelerates 1m/s^2[/color]. determine magnitude of each force.
answer: 120 N , 100 N

okay...i need help with this. i am using Newtons law: force=mass x accelleration
i am trying to find force. mass is 20 kg and accelleration is 11 m/s. when i plug in that number, i get 220N. can someone please help?
You've got a couple of typos here, as noted above. Otherwise, you have solved for the net force when the body is accelerating at 11m/s^2. 220N is the net force. It is the algebraic sum of the 2 forces. You need to look at the 1m/s^2 acceleration case to get another equation before you can solve for the individual forces.
 
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