A rope is held from one end in such a way that the lower end just touches a table. The rope is then lowered onto the table with constant velocity. The force that is needed to hold the upper end of the rope is
A) equal to the weight of the portion of the rope that is not on the table.
B) greater than the weight of the portion of the rope that is not on the table.
C) less than the weight of the portion of the rope that is not on the table but not zero N.
D) zero N.
E) Cannot be determined without additional information.

Question

Quizplus · Accepted Answer

When the rope is held in such a way that the lower end touches the table, there is tension in the rope equal to the weight of the portion of the rope that is not on the table. As the rope is lowered onto the table with constant velocity, the tension in the rope remains the same. Therefore, the force needed to hold the upper end of the rope is the same as the tension in the rope, which is equal to the weight of the portion of the rope that is not on the table. Hence, the correct option is A) equal to the weight of the portion of the rope that is not on the table.

A Rope Is Held from One End in Such a Way