Inclined Plane Vector Problem: Understanding the Use of Trigonometric Functions

AI Thread Summary
The discussion clarifies the use of trigonometric functions, specifically sine and cosine, to resolve the weight of an object on an inclined plane into components parallel and perpendicular to the ramp. Weight remains constant, but its effects vary based on the angle of the incline, necessitating these calculations. The angle of friction is considered zero for a straight line, as there is no incline. The importance of defining coordinate axes parallel and normal to the ramp is emphasized for accurate analysis. Understanding these concepts is crucial for solving inclined plane problems effectively.
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Homework Statement
In picture
Relevant Equations
Cos(x), sin(x), angle addition/subtraction.
I'm not really asking for a solution for this problem I just want to clear up a confusion I have.

Why are they multiplying the weight by the sin and cosine of the 30-degree angle?
Isn't weight not affected by anything since it's constant?

Also is the angle of friction 0 because it's a straight line?

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Did you post the entire question and solution? It should state that the coordinates chosen are parallel to the ramp (x) and normal to the ramp (y). The use of sin and cos is to find the components of the weight in those directions.
 
haruspex said:
Did you post the entire question and solution? It should state that the coordinates chosen are parallel to the ramp (x) and normal to the ramp (y). The use of sin and cos is to find the components of the weight in those directions.
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sorry about that
 
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