How Do I Find the Horizontal Distance of a Bug on a Moving Ladder?

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Homework Help Overview

The problem involves a ladder leaning against a wall, with a bug climbing the ladder while the base of the ladder is being pulled away from the wall. The goal is to find the horizontal distance of the bug from the wall as a function of time, given the rates at which the bug climbs and the ladder's base moves.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • The original poster attempts to use the Pythagorean theorem to relate the distances involved but expresses uncertainty about how to proceed. Some participants suggest using trigonometric relationships or similar triangles to find the solution. There is also a discussion about the position of the bug along the ladder over time.

Discussion Status

Participants are exploring different methods to approach the problem, with some providing suggestions for using trigonometry or visualizing the scenario with diagrams. There is no explicit consensus on the best approach yet, but various lines of reasoning are being discussed.

Contextual Notes

The problem setup involves specific rates of movement for both the bug and the ladder, which are central to the discussion but have not been fully resolved in the conversation.

nicnic20
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Homework Statement



So I've seen this posted here already but I'm still completely clueless on how to start the problem.

Problem: A 30-foot ladder rests vertically against a wall. A bug starts at the bottom of the ladder and climbs up at a rate of 3.5 feet per minute. At the same time, the foot of the ladder is being pulled along the ground at a rate of 1.5 feet per minute until the top of the ladder reaches the ground. Let x be the distance of the bug from the wall at time t.



Question: Find the function x(t). This function gives the horizontal distance of the bug to the wall as a function of time, t.



Homework Equations





The Attempt at a Solution


So I'm not sure where to begin when finding x(t). I started with the Pythagorean theorem because of the obvious triangle and came up with x^2 + y^2= 30. Now I'm stuck.
 
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It's not that hard. Figure out how far the bug has gone along the ladder at time t. Then figure out what the cosine of the angle the ladder is sitting at time t. Use some trig. Or similar triangles, your choice. BTW I think we should call this "the famous bug problem". Let's give the bug his due.
 
I'll call it the famous bug on the infamous ladder problem.
I'm sure I am making it 100x more complicated than it actually is.


So I figured out the bug is at 3.5t/30 am I correct?
 
nicnic20 said:
I'll call it the famous bug on the infamous ladder problem.
I'm sure I am making it 100x more complicated than it actually is.


So I figured out the bug is at 3.5t/30 am I correct?

At time t the bug will be 3.5*t feet along the length of the ladder. The bottom of the ladder will be 1.5*t feet from the wall. If you draw a picture, you should see some right triangles to solve.
 

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