Finding this displacement on a v/t graph

AI Thread Summary
To determine displacement from a v/t graph, the area between the velocity line and the horizontal axis must be calculated, with areas below the axis counted as negative. The user initially calculated the area under the line but misunderstood that only the area between the line and the axis represents displacement. The correct approach involves summing the areas of triangles and rectangles formed by the graph, ensuring to account for any sections below the axis. The user initially arrived at an incorrect total of 171 or -171 meters. Clarification emphasizes the importance of accurately interpreting the areas in relation to the horizontal axis for proper displacement calculation.
jeffc93
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Homework Statement



2j3p8x2.gif


theres a picture of the graph and i need to determine the displacement of the object within the first 18seconds of it. (in meters)

Homework Equations



area below line is displacement (i thought?)

The Attempt at a Solution



i just did some basic things:

i found the height which is 18.

and then i found the areas of all the triangles and rectangles under the line and added them up and got 171 or -171 but its not right

any help?

any help would be greatly appreciated, therefore i could do the rest on my own :)
 
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Welcome to PF!

Hi jeffc93! Welcome to PF! :smile:
jeffc93 said:
area below line is displacement (i thought?)

Nope :redface: …

area between line and horizontal axis (with areas below the axis counting as negative) is displacement. :wink:
 
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