A 2.0-m rope is lying on a table.You pick up one end and start raising it vertically.How high above the table is the center of mass (or center of gravity)of the rope when half of the rope has lifted off the table?
A)0.25 m
B)0.50 m
C)0.75 m
D)1.0 m
E)1.5 m

Question

Quizplus · Accepted Answer

When half of the rope is lifted off the table, the center of mass of the lifted portion is at the midpoint of that half, which is 0.5 meters from the end being lifted. Since this is half of the rope, the midpoint is 1 meter from the end, making the center of mass 0.25 meters above the table.

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