Three particles are arranged on a coordinate system. Particle 1 has mass 2 kg and is located at (0,0) m. Particle 2 has mass 4 kg and is located at (3,0) m. Particle 3 has mass 6 kg and is located at (3,4) m. Find the coordinates of the COM
(2.5, 2) m.
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D
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D
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B
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What is Center of Mass?
The center of mass of an object or system is the point where mass is evenly distributed in all directions.
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The Formula for COM
x cm = ∑m i ∑m i x i
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drawing
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draw
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draw
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draw
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Forces are balanced if:
a) rightward forces are balanced by leftward forces b) upward forces are balanced by downward forces
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Normal Force
contact force of a surface pushing against object (ALWAYS PERPENDICULAR to surface)
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contact force that ALWAYS acts in opposite direction of sliding motion (or potential motion) between surfaces
Friction
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Steps for drawing free body diagrams:
1) draw only 1 object 2) draw 1 arrow for each force acting on object; pointing away from object 3) label each force
