"Published in Newark, California, USA"
The body of a 30° incline as shown in the figure is acted upon by a force P inclined at 20° with the horizontal. If P is resolved into components parallel and perpendicular to the incline and the value of the parallel component is 300 lbs., compute the value of the perpendicular component and of P.
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| Photo by Math Principles in Everyday Life |
Solution:
Did you notice that the direction of force P is not vertical nor horizontal? The direction of force P is 20° above the horizontal towards to the body or block. Let's isolate the given figure so that we can draw the x and y components of force P as follows
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| Photo by Math Principles in Everyday Life |
If Px = 300 lbs., then we can solve for the value of P by using trigonometric functions of a right triangle as follows
Therefore, by using trigonometric functions of a right triangle, the value of Py is
