Finding the y- component of velocity

AI Thread Summary
To find the y-component of velocity for a boat moving at a 60° angle with a known x-component of 5 m/s, the tangent function should be used. The correct formula is y = x * tan(60°), leading to the calculation of the y-component as 5 * √3 m/s. The initial approach using cosine was incorrect since it pertains to the adjacent side rather than the opposite side. A diagram can aid in visualizing the problem and applying the correct trigonometric functions. The final answer for the y-component is 5√3 m/s.
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Homework Statement



A boat moves at an angle of 60° to a horizontal line. The x component of the boat's velocity is 5 m/s. What is its y component of velocity?
Question 25 answers

10 m/s

10 √3 m/s

5 √3 m/s

5 m/s



Homework Equations



How exactly do I find the y-component for this problem?

The Attempt at a Solution


I originally drew a diagram of a triangle and came up with the equation cos 60=x/5, when I tried to solve for x I got 2.5 m/s. This isn't one of the solutions available so I am thinking I'm not using the correct equation.
 
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cos 60 should be equal to the vector adjacent to the 60 degree angle divided by the hypotenuse. You're looking for the vector opposite from the angle, so there's a different operation for that.
 
Flipmeister said:
cos 60 should be equal to the vector adjacent to the 60 degree angle divided by the hypotenuse. You're looking for the vector opposite from the angle, so there's a different operation for that.

i would start out with a diagram, showing the angle and x and y velocities.

it makes the trig much easier
 
Hi,
as your not given the hypotenuse your are only given an angle and the x component you need to use the tangent function

SOH CAH TOA

This then becomes 5 * Tan(60) = the y component you are after.

71vk0.jpg


I hope that helps and more importantly I hope I am right
thanks
Mr C
 
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