Finding the direction and velocity of wind using vectors question

AI Thread Summary
A person traveling east at 4.0 km/hr perceives the wind coming from the north, while at double the speed, the wind appears to come from the northeast. The key equation involves understanding that the velocity of wind relative to the person is equal to the velocity of wind relative to the ground minus the person's velocity. To solve the problem, one can visualize the situation using vector diagrams to form a triangle representing the velocities. This approach clarifies the relationship between the wind's direction and velocity relative to the moving observer. Understanding these vector relationships is crucial for determining the wind's actual direction and speed.
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Homework Statement



A person, traveling eastward at a rate of 4.0 km/hr, observes that the wind seems to blow directly from the north; on doubling his speed the wind appears to come from the northeast; determine the direction of the wind and its velocity.

Homework Equations





The Attempt at a Solution



My teacher has actually given us the answers on this question. However, I am stuck at the point where she says the
Velocity of wind relative to person = Velocity of wind relative to the ground - velocity of person relative to the ground.

I just can't understand this at all! Please help!
Thank you in advance!
 
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welcome to pf!

hi shy9488! welcome to pf! :smile:
shy9488 said:
… I am stuck at the point where she says the
Velocity of wind relative to person = Velocity of wind relative to the ground - velocity of person relative to the ground.

I just can't understand this at all! Please help!

it means that if you draw the three vectors (with arrows), then they join up to form a vector triangle

(and when the question says "observes that the wind seems to blow directly from the north", it means that the velocity of the wind relative to the person is north)

see the pf library, or wikipedia, for details :wink:​
 

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