Geometry Discrete Problem Thanks

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The discussion focuses on solving a physics problem involving an advertising sign supported by a steel brace and a wire. Participants emphasize the importance of drawing a free body diagram to visualize the forces acting on the sign, including tension and compression. A common misconception is clarified: the compression force in the brace acts outward, not inward towards the building. Users are encouraged to share their attempts at solving the problem and to use trigonometry to resolve the forces into a right triangle. Overall, understanding the vector directions and applying trigonometric principles are key to finding the tension in the wire and the compression in the brace.
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An Advertising sign is supported by a horizontal steel brace extending at right angles from the side of a building, and by a wire attached to the building above the brace at an angel of 25. If the force of gravity on the sign is 850N, find the Tension in the wire and the compression in the steel brace
 
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You should post your attempts at the problem as well, not just the question. But to get you started, draw a free body diagram around the end of the brace, where the steel, wire and advertising sign all meet, and resolve the forces.
 
Karma said:
An Advertising sign is supported by a horizontal steel brace extending at right angles from the side of a building, and by a wire attached to the building above the brace at an angel of 25. If the force of gravity on the sign is 850N, find the Tension in the wire and the compression in the steel brace
You have the EXACT same textbook as me!

This question is actually really easy once you understand a couple key things. You must first draw a diagram, and remember your arrows on your vectors. Also, it is a common misconception that for these types of problems the compression force is inwards (so in this case toward the building). Actually, the force is outwards. Once you realize this you can simply set up your vectors forming a right angle triangle...use trig to solve.

Post the steps you have, I'm not going to give you the answer, so I'll check your work with mine (my math teacher confirmed mine is correct). Good luck.
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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