How Do Asymmetrical Stepladder Masses Affect Vertical Forces?

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The discussion focuses on analyzing the vertical forces acting on an asymmetrical stepladder with two legs of unequal masses, where leg BC is heavier at 34.7 kg and leg AB is lighter at 21.5 kg. The ladder is in equilibrium, meaning the sum of vertical forces and the sum of torques must equal zero. To solve for the vertical forces on the legs, one can treat the ladder as a rigid body and consider the center of gravity for each leg. A suitable axis for calculating torques is suggested to simplify the analysis. The conversation emphasizes the importance of understanding equilibrium conditions in determining the forces involved.
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A ladder consists of two legs, AB and BC, that are pinned at joint B and held together by a massless wire between D and E. The two legs are uniform and have the same length (so the ladder forms an isosceles triangle), but the legs have unequal masses. The heavier of the two legs, BC, has a mass of 34.7 kg and is shown shaded gray. The other leg, AB, has a mass of 21.5 kg. The ladder is standing on a smooth floor. The dimensions of the ladder are shown below.

The top of the ladder B is y = 2.45 m above the floor, the distance AC (the base of the ladder) is x = 1.49 m, and the cross brace DE is h = 1.35 m above the floor.

What are the vertical forces on the two legs? (Use "+" if the force component is up, "-" if it is down.) (Ay and Cy)


I know that all of the "internal" forces and torques cancel out if you look at the ladder as a single rigid body. You can then treat it as "center of gravity" problem where two masses are supported on a massless board of length 1.49 m. But I am not sure how to solve it like this? Please Help. Thanks.
 

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Since the ladder is in equilibrium, you know that (1) the sum of the forces in any direction must be zero, and (2) the sum of the torques about any point must be zero. Since each leg is uniform, you can treat its weight as acting at its center. What's a good point to pick as your axis for finding torques?

Give it a shot.
 
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