In a Force vs Distance graph, is work the area underneath?

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SUMMARY

In a Force vs Distance graph, the work done is represented by the area under the curve, which is calculated using the formula W = F x d. The discussion clarifies that for varying forces, such as in the case of a shovel being pushed into the ground, the area can be approximated using the trapezoidal rule or by calculating the area of geometric shapes formed under the graph. The correct calculation for the work done over a distance of 0.06 m, given the varying forces, results in 0.36 J, as opposed to incorrect methods yielding 1.12 J and 0.48 J.

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  • Familiarity with basic calculus concepts for area under curves
  • Ability to apply the trapezoidal rule for approximating areas
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1. Homework Statement

In a Force vs Distance graph, is work the area underneath?
A person pushes a shovel into the ground to do some spring gardening. He applies a force to the shovel over the following displacement.

0 N - 0 m
4 N - .02 m
8 N - .04 m
12 N - .06 m

Draw a graph, and find work done by man on shovel over the .06 m. 2. Homework Equations
F x d = W

The Attempt at a Solution


So at first, I calculated all the work, using F x d, and added all of them together, but he said that was wrong. And after we multiplied each of the the force by .02 since its in intervals and then added, but apparently we were wrong again. We have drawn a graph, that is a straight line. Is the area underneath the work? If so, why? Thanks
 
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Yes, the area underneath the graphed line is the work, tho' you should be using the x-axis for the distance, and the y-axis for the force(that's simply the common convention). Can you show me how you arrived at yoru answer?
 
why is distance on the x axis?

well, if i use the area under the graph, then it'd be

distance x force / 2

.06 x 12 / 2

.36 J

But can someone explain why? Since i had come up with 1.12 J when adding them all together, and .48 J when using the interval method
 
I'm not particularly sure how you came up with 0.36J and 1.12. Can you show me how you arrived at those answers both mathematically and with words? Keep in mind that the equation W = Fcos(\theta)\Delta x is used to find the work done by a constant force. From 0 to 0.06m, the force varies, and this is why we use the interval method. Does that make sense?
 
I'm actually not sure what I did, but after reading what you wrote and doing a bit of asking around, I finally have the answer. Thank you for your help! Much appreciated!
 

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