Angle for Impending Motion on Inclined Plane with Attached Blocks

In summary, the conversation discusses the determination of the angle for impending motion of block B, which is attached to block A and rests on a surface with a coefficient of static friction of 0.20. The calculation involves summing the parallel forces on block B, including tension, weight, normal force, and the force from block A, and setting it equal to 0. There is also a discussion about a missing equation for the perpendicular-to-ramp direction, which is necessary for calculating friction.
  • #1
physicsss
319
0
The 8 kg block A is attached to link AC and rests on the 12-kg block B. Knowing that the coefficient of static friction is 0.20 between all surfaces of contact and neglecting the mass of the link, determine the angle for which motion of block B is impending.

Can someone check my equations and see if they are OK? There's something screwy with the numbers I'm pluggin in so if you can tell me what you should get, I will be grateful. Thanks.

Link to my work: http://img507.imageshack.us/img507/9884/img0801copy2bm.jpg [Broken]
 
Last edited by a moderator:
Physics news on Phys.org
  • #2
For impending motion, block B has
Sum of F parallel = - T + 2.5 W_A sin(theta) - mu N - F_1 cos(theta) = 0 .

Somehow you forgot to sum the Forces in that direction?
 
  • #3
The equation or the pluggin in of the numbers?
 
  • #4
I didn't see any Sum of Forces equation for block B
in the parallel-to-the-ramp direction (perp to N).
 
  • #5
Why do I need it?
 
  • #6
WHAT? That's the direction that the acceleration is to occur in!

The perp-to-ramp component Force Sum is just to get the Friction -
if the ramp was frictionless you wouldn't have needed it at all!
 
  • #7
That's the last equation labeled translational force...
 
  • #8
anyone? :-/
 

1. What is an inclined plane?

An inclined plane is a simple machine that consists of a flat surface that is tilted at an angle. It is used to reduce the effort needed to lift an object by increasing the distance over which the force is applied.

2. How does an inclined plane work?

An inclined plane works by reducing the amount of force needed to lift an object. By increasing the distance over which the force is applied, the amount of force needed is decreased, making it easier to lift the object.

3. What are the two blocks on an inclined plane?

The two blocks on an inclined plane refer to the objects that are placed on the inclined plane. One object is typically placed at the bottom of the inclined plane, and the other object is placed at the top.

4. Why are two blocks used on an inclined plane?

Two blocks are used on an inclined plane to demonstrate the concept of mechanical advantage. By using two different objects with different masses, it can be shown that the object with the larger mass requires less force to lift when placed on the inclined plane.

5. What is the relationship between the angle of the inclined plane and the force needed to lift the object?

The relationship between the angle of the inclined plane and the force needed to lift the object is inversely proportional. As the angle of the inclined plane increases, the force needed to lift the object decreases. This is due to the increased distance over which the force is applied.

Similar threads

  • Introductory Physics Homework Help
Replies
27
Views
5K
  • Introductory Physics Homework Help
Replies
7
Views
1K
  • Introductory Physics Homework Help
Replies
5
Views
2K
Replies
19
Views
3K
Replies
5
Views
1K
  • Introductory Physics Homework Help
Replies
7
Views
5K
  • Introductory Physics Homework Help
Replies
19
Views
2K
  • Introductory Physics Homework Help
Replies
16
Views
4K
  • Introductory Physics Homework Help
Replies
13
Views
5K
Replies
18
Views
1K
Back
Top