Understanding Freebody Diagrams: Solving for Forces & Direction | Quick Help

  • Thread starter 0338jw
  • Start date
  • Tags
    Diagrams
In summary, the conversation discussed the concept of summation of forces in freebody diagrams and whether the order in which the forces are listed matters. The conclusion was that the order does not matter as long as the signs are correct, and the addition of real numbers is commutative. The question also arose about the horizontal component of gravity, to which it was confirmed that it does exist. The conversation ended with the suggestion to first write the sum of the forces vectorially, then breaking it down into components and accounting for signed quantities. The participants expressed their gratitude for the helpful and quick responses.
  • #1
0338jw
42
0
Hello all. I had a question about freebody diagrams. I know how to draw them and solve for forces/acceleration/mass/friction but one thing I was confused about is when you list summation of forces in either X or Y direction if there's a specific order to list them in, or if it matters. I know to list forces like Force of tension - Force friction =max but where would the X component of gravity fit in? I know the +/- symbols account for direction of the vector but does it matter in which order the forces are put in? Thanks for any and all help in advance! Hoping for a quick reply.
 
Physics news on Phys.org
  • #2
real numbers are associative and commutative (a mathematical property meaning it doesn't matter in what order you add/subtract them). 1 + 2 = 3 as does 2 +1
 
Last edited:
  • #3
Order doesn't matter (as long as you have the signs right). Addition is commutative: A + B = B + A.

(Does gravity have a horizontal component? :wink:)
 
  • #4
Doc Al said:
Order doesn't matter (as long as you have the signs right). Addition is commutative: A + B = B + A.

(Does gravity have a horizontal component? :wink:)

Thanks guys! I had a feeling I wasn't just getting lucky each time :D.

It sure does when you turn your paper theta degrees, haha.

I look forward to posting more and contributing, as I was a lurker before this. You guys are very helpful and damn fast! Again, thanks guys.
 
  • #5
I'd suggest that you first write the "SUM of the Forces" vectorially.
[tex]\vec T+ \vec W+\vec f[/tex] (order not important), then choose your axes, then break into components...
[tex] T_x+ W_x+ f_x[/tex] (keep order for bookkeeping)
[tex] T_y+ W_y+f_y[/tex],
then write "0" or the appropriate signed quantities for certain components.
 

FAQ: Understanding Freebody Diagrams: Solving for Forces & Direction | Quick Help

What is a freebody diagram?

A freebody diagram is a visual representation of all the forces acting on an object. It helps to simplify a complex system and understand the net force acting on the object.

Why is it important to understand freebody diagrams?

Freebody diagrams are essential in solving problems involving forces and motion. They help to identify all the forces acting on an object and determine the net force and its direction, which is crucial in understanding the motion of the object.

How do you draw a freebody diagram?

To draw a freebody diagram, you need to identify all the forces acting on the object and draw them as arrows pointing in the direction of the force. The length of the arrow represents the magnitude of the force, and the arrow's direction represents the force's direction. Remember to label each force and ensure that the forces are balanced.

What is the difference between a freebody diagram and a force diagram?

A freebody diagram only shows the forces acting on an object, while a force diagram also includes the object's acceleration. In a freebody diagram, all the forces are represented as vectors, while in a force diagram, they are represented as arrows without any specific direction.

How can you use freebody diagrams to solve for forces and directions?

To solve for forces and directions using a freebody diagram, you need to apply Newton's laws of motion. First, identify all the forces acting on the object and their directions. Then, use the equations of motion to calculate the net force and determine the object's acceleration. From there, you can solve for the missing forces or directions using trigonometric functions.

Similar threads

I People pulling rope, one in a perpendicular direction
Replies
16
Views
3K
A Understanding Force Diagrams for Hydraulic Cylinder Selection
Replies
2
Views
2K
B Modeling Quickly Pushed Boxes: A Beginner's Guide
Replies
15
Views
5K
A How to know the number of Feynman diagrams for a given order?
Replies
0
Views
694
G-force diagram on a roller coaster?
Replies
5
Views
2K
Block on top of an inclined plane, with a rough surface, that moves with constant acceleration
2
Replies
41
Views
2K
I Teaching Minkowski diagrams effectively
Replies
15
Views
1K
A-level Maths Mechanics: Prevent Block from Sliding Down Inclined Plane
Replies
30
Views
2K
Drawing diagrams in physics is so difficult for me!
Replies
13
Views
2K
Understanding Free Body Diagrams: Explaining the Forces on a Compressed Board
Replies
7
Views
2K

Hot Threads

Recent Insights

Back
Top