Magnitude and Direction, Canoe on River

[ap_physics]

Homework Statement

A canoe has a velocity of 0.35 m/s southwest relative to the earth. The canoe is on a river that is flowing 0.65 m/s east relative to the earth. Find the velocity (magnitude and direction) of the canoe relative to the river.

The Attempt at a Solution

0.930985 is the magnitude.
Then I have no clue how to get the angle in terms of counterclockwise from east.

Thanks very much in advance!

 

[gneill]

Homework Statement

A canoe has a velocity of 0.35 m/s southwest relative to the earth. The canoe is on a river that is flowing 0.65 m/s east relative to the earth. Find the velocity (magnitude and direction) of the canoe relative to the river.

The Attempt at a Solution

0.930985 is the magnitude.
Then I have no clue how to get the angle in terms of counterclockwise from east.

Thanks very much in advance!

Hi ap_physics; Welcome to Physics Forums.

How did you arrive at an angle of 315 degrees for the canoe's velocity? I would have thought that "southwest" would be halfway between south and west.

Edit: I see you've edited your original so that the angles of the vectors are no longer shown. Perhaps you could just explain your approach to the problem?

 

[ap_physics]

Well, I posted my attempt earlier, but it was wrong, and I was given the answer for the velocity by my teacher, as it was too complicated for our level. But, he says I can still find the angle. But, I don't know which formula to use.

 

[gneill]

Well, I posted my attempt earlier, but it was wrong, and I was given the answer for the velocity by my teacher, as it was too complicated for our level. But, he says I can still find the angle. But, I don't know which formula to use.

Okay, what have you learned so far about adding and subtracting vectors? Have you learned how to determine their angles from their x and y components?