Is relative velocity confusing in multiple vector systems?

AI Thread Summary
The discussion centers on the confusion surrounding relative velocity in multiple vector systems, particularly in the context of a woman running in the rain. Participants question the accuracy of vector representations, specifically the placement of angles α and β, and suggest that the vector for the woman should be adjusted to reflect her movement against the rain. It is emphasized that the horizontal component of the rain's velocity appears larger to the woman than to an observer on the ground, affecting the perceived angle of the rain. The formula for the speed of the rain concerning the ground is reiterated, highlighting the relationship between the rain's velocity relative to the woman and the woman's own speed. Overall, the complexities of relative velocity in vector systems continue to challenge understanding.
Hijaz Aslam
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Are the vectors resolved correctly? I get a different answer to this question(well my diagram itself is different). How can ##\beta## be greater than ##\alpha##?

Isn't it that here ##\alpha## should be in place of ##\beta## and ##\beta## in place of ##\alpha## and both ##V(rain,woman)## and ##V(rain)## should be in each others place?
 
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I believe that the diagram is wrong. The V(woman) vector should be transported to the right, starting at the tip of V(rain), and the sum should be constructed putting the end of V(woman) at the tip of V(rain). As the vectors of the picture seem to be to scale, the sum vector will lean to the right, clearly...
 
The speed of the rain in respect to ground vg is given by
v_g=v_rw+v_w

where v_rw is the speed of the rain in respect to the woman and v_w is the speed of the woman.
Take these as velocities (vectors) and this is what they have there.

If the woman runs against the rain, the horizontal component of the rain's velocity should be larger from the point of view of the woman than from the ground. The vertical component is not changed. So the angle is larger.
 
nasu said:
The speed of the rain in respect to ground vg is given by
v_g=v_rw+v_w

where v_rw is the speed of the rain in respect to the woman and v_w is the speed of the woman.
Take these as velocities (vectors) and this is what they have there.

If the woman runs against the rain, the horizontal component of the rain's velocity should be larger from the point of view of the woman than from the ground. The vertical component is not changed. So the angle is larger.

Yes, I was wrong in my post above... Imagining the rain falling vertically, running in any direction will result in the angle perceived by the runner growing more and more horizontal the faster he runs...
 
nasu said:
The speed of the rain in respect to ground vg is given by
v_g=v_rw+v_w

where v_rw is the speed of the rain in respect to the woman and v_w is the speed of the woman.
Take these as velocities (vectors) and this is what they have there.

If the woman runs against the rain, the horizontal component of the rain's velocity should be larger from the point of view of the woman than from the ground. The vertical component is not changed. So the angle is larger.
Oh yes. This relative velocity baffles me always :(

Nasu - thanks for your reply. Your answer cleared it. If you don't mind can you look into this problem in my thread ( https://www.physicsforums.com/threa...taining-multiple-vectors.777125/#post-4887266 ) Relative velocity catches me there too :( .
 
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