Calculate Paul's Speed with Work and Energy: Friction & Tension on a Mat

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To calculate Paul's speed after being pulled 2.60 m, the net force acting on the system is determined to be 5.73 N. This net force should be used to calculate the work done on Paul by multiplying it by the distance of 2.60 m. The work done translates into a change in kinetic energy, which can be expressed as the difference between the final and initial kinetic energy. By applying the work-energy principle, the final speed can be derived from the change in kinetic energy. The correct approach involves using the net force to find work, then solving for speed through kinetic energy calculations.
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Susan's 13.0 kg baby brother Paul sits on a mat. Susan pulls the mat across the floor using a rope that is angled 30 degrees above the floor. The tension is a constant 30.0 N and the coefficient of friction is 0.180.

Use work and energy to find Paul's speed after being pulled 2.60 m


So far I found the forces acting on the system to be:

Y:
127.5N down due to gravity
15N up due to tension
112.5N normal force
X:
25.98 due to tension
-20.25 due to friction

So I get a net force of 5.73N which I thought if I divided by the mass of 13kg it would give me that speed, but that is wrong. I am stuck here guys.

Thanks in advance for the help
 
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Force divided by mass is acceleration.

The instructions say to use work and energy. Now that you have the net force, use that to calculate the work. And then use the change in kinetic energy to calculate the speed.
 
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