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iop360
See Picture Attached: If the force acting along the leg is 360N, determine the component along the y axis Answer: 344N (Explanation needed!)
Is it definitely 344N? In general, the vertical force up (y) must equal the vertical down (so its balanced). As 360N is not down, we must find the contribution of that amount in the vertical direction. It is called resolving a force and is done by trigonometry. Draw a triangle: 360N is the hypotenuse, 'y' is the adjacent and the other side is the opposite (to make a right angled triangle.) The angle between hypotenuse and adjacent is 30 degrees. (90 - 60). So; \[cos \theta = \frac{adj}{hyp} \] I.e. y = cos30 x 360 = 312N... I am a physics teacher, I cannot work out where 344N could come from with the information given...
I have no idea how they got 344N either. I'm also not so sure why you're using cos and not sin...maybe I'm misunderstand the image. Here's how I see it: |dw:1359074375524:dw|