Applied force in horizontal direction on block on a inclined plane.

AI Thread Summary
A 10kg block on a frictionless inclined plane at 32 degrees is subjected to a horizontal force of 120N, prompting a discussion on calculating its acceleration. The net force acting on the block is derived from the gravitational component along the incline and the horizontal force's component along the plane. The calculation involves resolving the horizontal force into components, leading to the realization that the correct approach is to use xcos32 to find the effective force along the incline. The confusion arises from misunderstanding the relationship between the applied force and its components. Ultimately, the correct acceleration of the block is determined to be 5.0 m/s².
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Homework Statement


10kg block on a inclined plane (32degrees) (frictionless) and an applied force 120N horizontally. What is acceleration?


Homework Equations



Fnet = ma

The Attempt at a Solution



mgsin32 = 51.9N (from mg)
From applied force, in the same plane, we have xcos32=120 therefore, x = 141.5
141.5-51.9=ma
a=9m/s^2 but the answer is 5.0m/s^2
 
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get_physical said:
... From applied force, in the same plane, we have xcos32=120 therefore, x = 141.5...

Explain how you got xcos32=120
 
because the horizontal force is 120N, so I need to find the hypotenuse component. the angle in that triangle is also 32, so xcos32 = 120
 
Think carefully.

The horizontal force of 120N has a component along the plane and another component perpendicular to the plane and you need to find the component along the plane.
 
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Let me think...
 
Remember that when a force is resolved into components, the force itself will be what you are calling the 'hypotenuse'.
 
Oh I get it now! Thank you!
 
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