Situation diagram and free body diagram

AI Thread Summary
A situation diagram represents the overall context of a physics problem, while a free body diagram focuses specifically on the forces acting on a single object, excluding the forces it exerts. In a free body diagram, the chosen object is depicted with all external forces acting on it, such as gravity and tension from supporting threads, but not the forces it exerts on other objects. Understanding the distinction is crucial for correctly analyzing physical scenarios. The conversation highlights the need for clarity in differentiating these two types of diagrams in physics. Proper use of both diagrams aids in solving complex problems effectively.
Googl
Messages
111
Reaction score
1
Hi all,

What is the difference between a situation diagram and free body diagram? I understand what a free body diagram is.

Thanks.
 
Physics news on Phys.org
I don't understand what a "situation diagram" is. Perhaps it's any kind of diagram of a physics problem.

For a free body diagram, you pick some object to be the "free body" and then you draw all the forces acting upon the body and do not draw the forces exerted by the body itself. For example if the "free body" is bar is suspended at its ends by threads, you draw the force of gravity on the bar and the force of each thread on the bar. But you don't draw the forces that the body exerts on the threads or the forces that the other ends of the threads exert on the ceiling or whatever is holding them.
 

Thread '1:1 versus 2:1 Mechanical Advantage debate'

The rope is tied into the person (the load of 200 pounds) and the rope goes up from the person to a fixed pulley and back down to his hands. He hauls the rope to suspend himself in the air. What is the mechanical advantage of the system? The person will indeed only have to lift half of his body weight (roughly 100 pounds) because he now lessened the load by that same amount. This APPEARS to be a 2:1 because he can hold himself with half the force, but my question is: is that mechanical...
View full post »

Thread 'Newton's first law?'

Some physics textbook writer told me that Newton's first law applies only on bodies that feel no interactions at all. He said that if a body is on rest or moves in constant velocity, there is no external force acting on it. But I have heard another form of the law that says the net force acting on a body must be zero. This means there is interactions involved after all. So which one is correct?
View full post »
Thread 'Beam on an inclined plane'

Thread 'Beam on an inclined plane'

Hello! I have a question regarding a beam on an inclined plane. I was considering a beam resting on two supports attached to an inclined plane. I was almost sure that the lower support must be more loaded. My imagination about this problem is shown in the picture below. Here is how I wrote the condition of equilibrium forces: $$ \begin{cases} F_{g\parallel}=F_{t1}+F_{t2}, \\ F_{g\perp}=F_{r1}+F_{r2} \end{cases}. $$ On the other hand...
View full post »

Similar threads

I Force Generated By Leg Muscles in Free Body Diagrams
Replies
8
Views
2K
What is the free-body diagram for a massless pulley in free fall?
Replies
31
Views
4K
I Why does a free rigid body rotate only about its COM when F(ext) is applied?
Replies
7
Views
1K
B Confused about force body diagram for 2 body collision
Replies
6
Views
2K
Why are moments not included in free body diagrams?
Replies
31
Views
2K
Calculating Free Body Diagram Forces
Replies
4
Views
3K
How do I use a free body diagram in this case?
Replies
3
Views
2K
Can you me understand free body diagrams
Replies
2
Views
2K
B Newton's 3rd Law interactions with 2nd and 1st Law Partners
Replies
8
Views
2K
Why are these pulleys equivalent?
Replies
16
Views
1K

Hot Threads

Recent Insights

Back
Top