Help vectors year 1 Physics undergrad.

Click For Summary
SUMMARY

The discussion revolves around calculating the maximum allowed weight of a unit fastened to a roof at a 35-degree angle, ensuring that the perpendicular force does not exceed 425 N. The user initially calculated the downward force (W) as 348 N using the cosine function, but this was incorrect. The correct approach involves understanding the relationship between the weight of the unit and the perpendicular force exerted on the roof, emphasizing the need for accurate force diagram representation and calculations.

PREREQUISITES
  • Understanding of vector components in physics
  • Knowledge of trigonometric functions, specifically cosine
  • Ability to draw and interpret force diagrams
  • Familiarity with Newton's laws of motion
NEXT STEPS
  • Review the principles of vector resolution in physics
  • Study trigonometric identities and their applications in force calculations
  • Practice drawing and analyzing force diagrams for various scenarios
  • Explore Newton's laws of motion to understand force interactions
USEFUL FOR

This discussion is beneficial for first-year physics undergraduates, educators teaching introductory physics concepts, and anyone interested in mastering vector analysis and force calculations in real-world applications.

Eats Dirt
Messages
91
Reaction score
0

Homework Statement



a weight fastened to a roof 35 degrees above the horizontal, the weight is directed downward, in order that the unit not crush the roof tiles the component perpendicular to the roof can not exceed 425 N, What is the maximum allowed weight of the unit?


Homework Equations



Cos ... etc

The Attempt at a Solution



OK so let's name the force straight down which i will call W
the force perpendicular to the horizontal plane is 425 N i will call that J

so we find that angle between vector W and B is 35 degrees. so i use cos(35)=W/J
Jcos(35)=W
which means the force down is 348 N which issss... WRONG :( tips would be great i really don't understand this .
 
Physics news on Phys.org
Draw a force diagram. You're basically on the right track but seem to have ended up with the "unit" weighing less than the perpendicular force it exerts on the roof! See if you can work out what's gone wrong.
 
Remember Cos is adjacent / hypoteneus. You may want to check your workings again
 

Similar threads

How Much Weight Can the Air-Conditioning Unit on a Sloped Roof Hold?
  • · Replies 7 ·
Replies
7
Views
7K
Relation between the velocity vector and the acceleration vector of an object
  • · Replies 1 ·
Replies
1
Views
916
Calculate electric force using Coulomb's law (vector components are the struggle)
  • · Replies 3 ·
Replies
3
Views
2K
Distance an object travels after sliding and falling from roof
  • · Replies 8 ·
Replies
8
Views
3K
Find the missing force when the boy is pulled
  • · Replies 35 ·
2
Replies
35
Views
4K
Find coefficient of kinetic friction of block and ramp.
  • · Replies 9 ·
Replies
9
Views
4K
Calculating P for an Aircraft Flying in a Circular Motion
  • · Replies 9 ·
Replies
9
Views
5K
Force on a rod attached to a pivot.
  • · Replies 2 ·
Replies
2
Views
3K
Solving Impulse & Power: mΔv vs. FΔt
  • · Replies 2 ·
Replies
2
Views
2K
Help (: adding vectors components.... angles, drawing.
  • · Replies 8 ·
Replies
8
Views
2K