How to Calculate Work from F vs x Graph?

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To calculate work from a force versus displacement graph, the area under the curve between the specified points must be determined. The work done is the sum of the areas of the triangles formed by the force values at the given displacements. For the positive force triangle, both force and displacement are positive, while for the negative force triangle, the force is negative and displacement is positive. The total work is the sum of the work calculated from the two segments of the graph. Understanding the shape of the area under the curve is essential for accurate calculation.
MLash

Homework Statement


x1= -2, x2= 2

F1= 1, F2= -2

Graph in uploaded image

Homework Equations


w= F* del x* cos(theta)

The Attempt at a Solution


I am trying to find the area under the points of F and x but it has an irregular shape and i don't know what to do? Should i do w= (f1-f2)(del x)?[/B]
 

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MLash said:
w= F* del x* cos(theta)
The general form of work is
$$W=\int_{x_{1}}^{x_{2}}\mathbf{F}\cdot d\mathbf{x}$$
Thus if you have a graph of ##F## vs. displacement. The work is the area under the curve from the staring position ##x_{1}## to the final position ##x_{2}##.
 
MLash said:

Homework Statement


x1= -2, x2= 2

F1= 1, F2= -2

Graph in uploaded image

Homework Equations


w= F* del x* cos(theta)

The Attempt at a Solution


I am trying to find the area under the points of F and x but it has an irregular shape and i don't know what to do? Should i do w= (f1-f2)(del x)?[/B]
No, the applied force changes with the position. And both the displacement and the force are along the x axis.
The work is equal to the area between the graph of force and the x axis. You have to calculate the area of both triangles, the blue one and the yellow one. In case of the blue triangle, both the force and the displacement are positive, so cos(theta)=? W1=?
In case of the yellow triangle, the force is negative, the displacement is positive, so cos(theta)=? W2=?
The whole work is the sum of the works done from x=-2 to x=0 (W1) and from x=0 to x=2 (W2) .
upload_2017-10-25_6-13-19.png
 

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