How Do Two Ladders Hinged Together Maintain Equilibrium?

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In summary, the problem involves two straight uniform ladders, AC and BC, with equal weights that are in equilibrium with their feet, A and B, on rough horizontal ground and their tops freely hinged at C. The angles CAB and CBA are given as 60 and 30 degrees respectively, and the length of AB is l. The first part of the problem involves finding the vertical reactions at A and B by taking moments about point B. However, the second part of the problem, which asks for the magnitude and direction of the force exerted on BC by AC, is causing difficulty. The direction of this force is known to be 30 degrees below horizontal, but the value is not coming out correctly. The calculation involves
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xduckksx
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Homework Statement



Two straight uniform ladders, AC and BC have equal weights. THey stand in equilibrium with their feet, A and b, on rough horizontal ground and their tops freely hinged at C. Angle CAB=60, angle CBA=30 and AB=l.

a)Find the vertical reactions at A and B.
b)Find the magnitude and direction of the force exerted on BC by AC.

Homework Equations



Taking moments about various points, moment=Fd

The Attempt at a Solution



The first part isn't too hard, taking moments about B allows me to resolve the vertical reaction at A, similarly for b.

However, the second part is annoying me. It's clear that the direction of the force is 30degrees below horizontal, however I can't get the value right.
Ignoring the second ladder, taking moments about A, you get a vertical weight force halfway up the ladder which gives a moment which is seen in the perpendicular force at the top of the ladder. But this doesn't give me the correct answer for F, which is W/2
 
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  • #2
Show your FBD and derivations in detail, please. Why are you sure in the direction of the force between the ladders? Did you count with the moment of the horizontal forces, too?

ehild
 
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FAQ: How Do Two Ladders Hinged Together Maintain Equilibrium?

What is the purpose of ladders leaning together?

The purpose of ladders leaning together is to create a stable structure that can be used to reach higher areas or perform tasks that require a person to be elevated.

What is the correct angle for ladders leaning together?

The correct angle for ladders leaning together is approximately 75.5 degrees. This angle provides the best balance between stability and reach.

How do you safely position ladders leaning together?

To safely position ladders leaning together, make sure they are placed on a level surface and that the base of the ladders are securely anchored. The ladders should also overlap at least 3 feet and be tied together at the top for added stability.

What are the dangers of ladders leaning together?

The dangers of ladders leaning together include the risk of the ladders slipping or tipping over, causing injuries to the person using them. There is also a risk of the ladders becoming unbalanced or unstable if not properly positioned.

Can you use any type of ladder for leaning together?

No, it is important to use ladders that are specifically designed for leaning together, such as extension ladders. Using the wrong type of ladder can increase the risk of accidents and injuries.

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