What Force Must a Window Washer Exert to Ascend at Constant Speed?

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To determine the force a window washer must exert to ascend at constant speed, it's crucial to recognize that constant speed implies zero acceleration, leading to a net force of zero. The tension in the rope must equal the gravitational force acting on the combined mass of the washer and bucket, calculated as 617.4 N. However, the initial calculation was deemed incorrect, suggesting a need for a more detailed analysis. A free body diagram is recommended to visualize all forces acting on the system, including the woman, bucket, and cords. Properly identifying these forces will clarify the correct approach to solving the problem.
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Homework Statement



A window washer pulls herself upward using the bucket-pulley apparatus:

4-40.gif


The mass of the person plus the bucket is 63 kg.

(a) How hard must she pull downward to raise herself slowly at constant speed?

Homework Equations



F = m(a)

The Attempt at a Solution



I figured that since she wants to raise herself at constant speed, that makes her acceleration equal to zero. Which means Fnet=0=Ftension-Fgravity, so Ftension=Fgravity. F gravity=9.8(63)=617.4 N, but it says I have the wrong answer.

Thanks in advance for the help.
 
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meganw said:

Homework Statement



A window washer pulls herself upward using the bucket-pulley apparatus:

4-40.gif


The mass of the person plus the bucket is 63 kg.

(a) How hard must she pull downward to raise herself slowly at constant speed?

Homework Equations



F = m(a)

The Attempt at a Solution



I figured that since she wants to raise herself at constant speed, that makes her acceleration equal to zero. Which means Fnet=0=Ftension-Fgravity, so Ftension=Fgravity. F gravity=9.8(63)=617.4 N, but it says I have the wrong answer.

Thanks in advance for the help.
you need to draw a good free body diagram. Isolate the woman , bucket and both cords by drawing a circle around them that cuts thru the cords, and identify all forces acting.
 
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