What is the Vector Sum of Two Vectors with Equal Magnitude and Different Angles?

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The discussion revolves around calculating the vector sum of two vectors with equal magnitudes of 29 m at angles of 31° and 105°. The user attempts to find the x and y components using the equations x = 29cos(31°) + 29cos(105°) and y = 29sin(31°) + 29sin(105°). However, they express confusion over the correctness of their calculations, as their input into a system called "lon capa" returned an error. The user suspects a possible mistake in distinguishing between degrees and radians but believes their approach is sound. The conversation highlights the importance of careful component analysis in vector addition.
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Homework Statement


The two vectors a and b in the figure have equal magnitude of 29 m and the angles are θ1 = 31° and θ2 = 105°. Find the x-component of their vector sum r. Find y-component sum. Magnitude of the vector sum? Find the angle that their vector sum r makes with the positive direction of the x-axis.


Homework Equations





The Attempt at a Solution



Ok i am confused as to why this won't work.
x = 29cos31 + 29cos105
y = 29sin31 + 29sin105

The second vector/magnitude points towards the y-axis and the first one points away. i can not seem to insert a picture.
 
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Looks good to me. Why do you think that's wrong? I'm assuming you're not making a simple mistake like confusing degrees and radians.
 
i mean i think it is right. i put that answer into lon capa and it said it was wrong, so i figured i was doing something wrong.
 
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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