# Very interesting incline problem

• jakeyboy
In summary, using the given information, the acceleration of the system was calculated to be -0.63, indicating that the system would be decelerating. However, this doesn't make sense as friction would change directions. The assumption that the system moves to the left was made, but this resulted in a negative acceleration again. Therefore, it is necessary to consider static friction and see if the system can be in rest assuming this type of friction.
jakeyboy

## Homework Statement

Find the acceleration of the system. Friction constant of incline is 0.2

## Homework Equations

Force of friction = 0.2 * 7 * 9.8 * cos30 = 11.88N
Force of gravity pulling down 7kg weight = 7 * 9.8 * sin30 = 34.3N
Force of gravity pulling down 4kg weight = 4 * 9.8 = 39.2

## The Attempt at a Solution

Since Fg4 > Fg7 then the system should accelerate towards the right.

Net Force = Fg4 - Fg7 - Ffriction = m4+7a

39.2 - 34.3 - 11.88 = (4+7)a
a = -0.63

It doesn't make sense that a is negative, because that would mean the system would be accelerating towards the left, and friction would change directions.

Try to get the acceleration with the assumption that the system moves to the left. You might get a negative value again. It has sense as you assumed that the system moves when equating Ffriction =μN, that is, you used kinetic friction. Assuming that the system was in motion at the beginning, negative acceleration means that it decelerates and will stop. After it stopped, the friction is static. See if the system can be in rest assuming static friction.

ehild

## 1. What is the "Very Interesting Incline Problem"?

The "Very Interesting Incline Problem" is a physics problem that involves calculating the acceleration and velocity of an object on an inclined plane. It is often used as a basic example to illustrate the application of Newton's Laws of Motion.

## 2. How do you solve the "Very Interesting Incline Problem"?

To solve the "Very Interesting Incline Problem", you must first draw a diagram of the inclined plane and label all the known and unknown variables. Then, you can use the equations of motion and trigonometry to calculate the acceleration and velocity of the object on the incline.

## 3. What are the key concepts involved in the "Very Interesting Incline Problem"?

The key concepts involved in the "Very Interesting Incline Problem" include Newton's Laws of Motion, the concept of forces and their components, and the use of trigonometry to analyze the motion of objects on inclined planes.

## 4. Are there any real-world applications of the "Very Interesting Incline Problem"?

Yes, the "Very Interesting Incline Problem" has many real-world applications. For example, it can be used to analyze the motion of objects on ramps, hills, or roller coasters. It is also relevant in fields such as engineering, construction, and sports.

## 5. What are some common mistakes when solving the "Very Interesting Incline Problem"?

Some common mistakes when solving the "Very Interesting Incline Problem" include forgetting to account for the effects of friction, using incorrect formulas or units, and not properly resolving forces into their components. It is important to carefully analyze the problem and double-check all calculations to avoid these mistakes.

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