# Interacting forces/inclined plane problem

• fsm
In summary, the problem involves a block of mass m resting on a 20 degree slope with coefficients of friction mu_s =0.80 and mu_k =0.50. It is connected via a massless string over a massless, frictionless pulley to a hanging block of mass 2.0 kg. The question is what acceleration will the system have when the minimum mass is nudged ever so slightly. The equation used is T-f_k-(mg*sin(theta))=m*a, where f_k=u_k*(mg*cos(theta)), but it cannot be solved alone due to 3 unknowns. Additional equations are needed, such as a free body diagram of the 2 Kg mass and considering the condition of the system before
fsm
I am having a promlem figuring the acceleration:

Figure shows a block of mass m resting on a 20 degree slope. The block has coefficients of friction mu_s =0.80 and mu_k =0.50 with the surface. It is connected via a massless string over a massless, frictionless pulley to a hanging block of mass 2.0 kg.

If this minimum mass is nudged ever so slightly, it will start being pulled up the incline. What acceleration will it have?

My equation I have is:

T-f_k-(mg*sin(theta))=m*a

where f_k=u_k*(mg*cos(theta))

I keep getting the answer wrong. Is it my formula?

fsm said:
I am having a promlem figuring the acceleration:

Figure shows a block of mass m resting on a 20 degree slope. The block has coefficients of friction mu_s =0.80 and mu_k =0.50 with the surface. It is connected via a massless string over a massless, frictionless pulley to a hanging block of mass 2.0 kg.

If this minimum mass is nudged ever so slightly, it will start being pulled up the incline. What acceleration will it have?

My equation I have is:

T-f_k-(mg*sin(theta))=m*a

where f_k=u_k*(mg*cos(theta))

I keep getting the answer wrong. Is it my formula?
Formula is looking good, real good. However, it can't be solved alone, since there are 3 unknowns (T, m, and a). You need a couple of more equations. How about an FBD of the 2 Kg mass after the nudge?? And, what can you conclude from the condition of the system BEFORE it was nudged??

I know the tension and mass. I'm trying to figure out the acceleration. When I use the above formula I get a wrong answer.

fsm said:
I know the tension and mass. I'm trying to figure out the acceleration. When I use the above formula I get a wrong answer.
How do you know the tension and how do you know the mass? Neither of them is given in the problem. Perhaps it is what you think you know that is leading you in the wrong direction.

## 1. What is the inclined plane problem?

The inclined plane problem is a physics problem that involves analyzing the forces acting on an object on an inclined plane. It is used to understand how gravity and friction affect the motion of objects on an inclined surface.

## 2. What are the forces involved in the inclined plane problem?

The forces involved in the inclined plane problem are the weight of the object, the normal force from the surface of the inclined plane, and the force of friction. These forces act in different directions and can either help or hinder the motion of the object.

## 3. How do you calculate the force of friction in the inclined plane problem?

The force of friction can be calculated using the equation Ff = μN, where μ is the coefficient of friction and N is the normal force. The coefficient of friction is a measure of the resistance to motion between two surfaces and can be found in tables or experimentally determined.

## 4. How do you determine the net force on an object on an inclined plane?

To determine the net force on an object on an inclined plane, you must first draw a free-body diagram and identify all the forces acting on the object. Then, you can use the equation ΣF = ma, where ΣF is the sum of all the forces and m is the mass of the object, to calculate the net force.

## 5. How does the angle of the inclined plane affect the forces on an object?

The angle of the inclined plane affects the forces on an object by changing the direction and magnitude of the forces. As the angle increases, the component of the weight force acting parallel to the plane also increases, making it harder for the object to move up the incline. Additionally, a steeper incline can also increase the force of friction acting against the motion of the object.

• Introductory Physics Homework Help
Replies
41
Views
683
• Introductory Physics Homework Help
Replies
18
Views
3K
• Introductory Physics Homework Help
Replies
2
Views
333
• Introductory Physics Homework Help
Replies
2
Views
1K
• Introductory Physics Homework Help
Replies
2
Views
893
• Introductory Physics Homework Help
Replies
3
Views
1K
• Introductory Physics Homework Help
Replies
11
Views
2K
• Introductory Physics Homework Help
Replies
4
Views
1K
• Introductory Physics Homework Help
Replies
16
Views
4K
• Introductory Physics Homework Help
Replies
8
Views
872