Motion in 2 Dimensions - Inclined Plane Pulleys

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Homework Help Overview

The discussion revolves around a physics problem involving motion in two dimensions, specifically focusing on a mass being hauled up an inclined plane using a pulley system. The problem includes the calculation of tension in the string while considering forces acting on the mass and the incline's angle.

Discussion Character

  • Exploratory, Conceptual clarification, Problem interpretation, Assumption checking

Approaches and Questions Raised

  • Participants discuss the components of weight acting on the mass, the role of tension, and the need for free body diagrams. There are attempts to apply Newton's second law and clarify the forces involved.

Discussion Status

The discussion is ongoing, with participants exploring different interpretations of the forces at play. Some have offered guidance on drawing free body diagrams and identifying forces, while others are questioning the calculations and assumptions made in the initial attempts.

Contextual Notes

Participants note the absence of friction due to the smooth surface and the implications of the incline's angle on the forces involved. There is also mention of the need for clarity in understanding the components of forces acting on the mass.

TheKovac
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Homework Statement


a Mess of 5kg is being hauled up a smooth invlined place at 30 degree to the horizontal with an acceleration of 1.5ms^-2 by mean of a string parallel to the incline:
a) What is tension in the string

Homework Equations


Fnet= ma
Rules of right angled triangles (SOC CAH TOA)
Any more?

The Attempt at a Solution


a)
=>Fnet = ma
Fnet = 5*1.6
Fnet = 8ms^-2
=>cos(theta)= O / H
cos60= O / 8
Tension = 16N = Wrong!
Answer = 32.5 N - How??
 
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The weight has 2 components, one is perpendicular to the plane, the other is down the plane. The tension acts up the plane. So the resultant force up the plane is?

(Also,the component down the plane is always weight*sine of the angle of inclination. Not cos)
 
2 Components. interesting..
That means the Perpendicular component
=> Fnet = ma
=> Fnet = 5*9.8
=> Fnet down = 49N

What next?
 
Before you approach questions like these, you must have a great understanding of how to draw freebody diagrams. For this question, Fnet = Ft + (-Fg parallel) = ma. If you do not understand where these forces are coming from, let me know and I'll draw you the freebody diagram.
 
Here, I attached a freebody diagram for the following question given that there is no force of friction due to the emphasis of a smooth surface and no coefficient of friction was given. Can you identify which forces are involved?
 

Attachments

Well I know that there are two main forces acting upon the pulley.

/|\
| Resistance Forces/ Tension
___
|___|

|
\|/ Gravity = 9.8ms Accel

These are the two I can think of, is there any more?
 

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