Static equlibrium with friction

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SUMMARY

The discussion focuses on solving a static equilibrium problem involving a 4.0 kg block held against a wall by a force F, with a coefficient of friction of 0.35. The key equations used are the sum of forces in the x-direction (Sum Fx = 0) and y-direction (Sum Fy = 0). A crucial detail is the 30° angle of force F with the vertical, which establishes a relationship between the vertical and horizontal components of the forces, allowing for the calculation of the normal force and the minimum force F required to prevent the block from sliding.

PREREQUISITES
  • Understanding of static equilibrium principles
  • Knowledge of friction coefficients and their application
  • Ability to resolve forces into components
  • Familiarity with Newton's laws of motion
NEXT STEPS
  • Study the concept of static friction and its role in equilibrium problems
  • Learn how to resolve forces at angles using trigonometric functions
  • Explore examples of static equilibrium problems involving multiple forces
  • Investigate the application of Newton's laws in real-world scenarios
USEFUL FOR

This discussion is beneficial for physics students, educators, and anyone interested in mastering static equilibrium problems, particularly those involving friction and angled forces.

canicon25
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Homework Statement



a 4.0kg block is held against a brick wall and is just kept from sliding down by the force F. The coefficient of friction is 0.35 between the block an d the wall.

Find the normal force and the minimum force F that will keep the block from sliding.

block.png


Homework Equations



Sum Fx = 0
Sum Fy = 0

The Attempt at a Solution



Fx=Fnormal
Fy+Ffriction=mg

uFx=Ffriction

Fy+uFx=39.2
 
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Hi canicon,
Your equations are correct, but one is missing.
It is given that the force encloses a 30° angle with the vertical. That means a relation between Fy and Fx. What is it? Adding this relation to the other equations, you can get Fx and Fy.
ehild
 
Last edited:

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