How does friction act between PA and AB in an equilibrium of forces system?

In summary, the conversation is about finding the value of the angle between PA and AB, and someone is seeking clarification on the direction of the frictional force between the two points. The person providing the response suggests assuming a direction and adjusting if necessary. It is also noted that Q is the center of AB and that friction acts parallel to the contact plane.
  • #1
nickyfernandezzz
18
2

Homework Statement


The original question was to find the value of the angle between PA and AB. I have a certain idea regarding how to find it, but first I have to identify all forces acting on the system and their directions. So, I would be grateful if someone can explain how the frictional force acts between PA
and AB.

MY ATTEMPT.
I got a start by marking the forces acting on the system but I can't figure out the direction of frictional force.
 

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  • #2
nickyfernandezzz said:

Homework Statement


The original question was to find the value of the angle between PA and AB. I have a certain idea regarding how to find it, but first I have to identify all forces acting on the system and their directions. So, I would be grateful if someone can explain how the frictional force acts between PA
and AB.

MY ATTEMPT.
I got a start by marking the forces acting on the system but I can't figure out the direction of frictional force.
Some verbal statement of the problem would be enlightening.
You have marked mg at point Q, but that does not look like the centre.
I assume you are asking about the direction of the frictional force at A. Generally speaking, you do not need to figure that out in advance. Just assume it is one way along the surface, and if you are wrong it should become obvious (and it might just be a matter of flipping the sign to get the right answer).
 
  • #3
haruspex said:
Some verbal statement of the problem would be enlightening.
You have marked mg at point Q, but that does not look like the centre.
I assume you are asking about the direction of the frictional force at A. Generally speaking, you do not need to figure that out in advance. Just assume it is one way along the surface, and if you are wrong it should become obvious (and it might just be a matter of flipping the sign to get the right answer).
I'm sorry for not being very clear. Actually, it was stated in the question that Q is the centre of AB.
So, is the friction acting ALONG the surface PA ( either upwards or downwards)?
 
  • #4

1. What is the concept of equilibrium of forces?

The concept of equilibrium of forces is based on Newton's First Law of Motion, which states that an object will remain at rest or continue moving at a constant velocity unless acted upon by an unbalanced force. In other words, for an object to be in equilibrium, the sum of all forces acting on it must be equal to zero.

2. How do you determine if an object is in equilibrium?

To determine if an object is in equilibrium, you must first identify all the forces acting on the object. Then, calculate the vector sum of these forces. If the sum is equal to zero, the object is in equilibrium. If the sum is not equal to zero, the object is experiencing a net force and is not in equilibrium.

3. What are the types of equilibrium?

There are three types of equilibrium: stable, unstable, and neutral. In stable equilibrium, an object will return to its original position after being displaced. In unstable equilibrium, an object will not return to its original position and will continue to move away. In neutral equilibrium, an object will remain in its new position after being displaced.

4. How does the concept of equilibrium apply to real-world scenarios?

The concept of equilibrium is applicable to various real-world scenarios, such as the balance of forces in a seesaw, the stability of structures, and the motion of objects on inclined planes. It is also crucial in understanding the behavior of objects in fluids, such as ships and airplanes, where maintaining equilibrium is essential for stability and control.

5. Can an object be in equilibrium if it is moving?

Yes, an object can be in equilibrium even if it is moving. This is known as dynamic equilibrium, where the object is moving at a constant velocity, meaning the net force acting on it is equal to zero. An example of this is a car moving at a constant speed on a flat road.

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