Vector Projections on the xy Plane and z Axis

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The discussion revolves around understanding vector projections in three-dimensional space, specifically on the xy plane and the z axis. The first vector, u, has a length of 6 and makes a 40-degree angle with the z axis, while its projection on the xy plane makes a 44-degree angle with the x axis. The second vector, v, has a projection of length 5 on the z axis and a projection of length 6 on the xy plane, making a 136-degree angle with the x axis. Participants express confusion regarding the interpretation of the problem's wording, particularly concerning the meaning of angles and lengths in relation to the z axis. Clarification on how to calculate these projections and angles is sought to resolve the confusion.
DarkSamurai
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Homework Statement


The vector u of length 6 makes an angle of 40 with the z axis; it's vector projection on the xy plane makes an angle of 44 degrees with the x axis.

The vector projection of a second vector v on the z axis has a length 5. The vector projection of v on the xy plane has a length of 6 and makes an angle of 136 with the x axis.

Homework Equations


u = <i, j, k>
v = <i, j, k>

The Attempt at a Solution


im confused on the wording of the problem but this is how I see it...

<5cos(44),0,5sin(40)>
<5cos(136), 0, 6>
 
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The first part confuses me, "length x makes an angle of theta with the z axis"

What does this mean? on the zx plane? So should I take the magnitude and then take the cos of the angle?
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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