What is the net displacement of the particle between 0 seconds and 80 seconds?
Here's the graph: http://i37.servimg.com/u/f37/16/73/53/52/graph410.png
Choices:
A. 160 meters
B. 80 meters
C. 40 meters
D. 20 meters
E. 0 meters

Question

What is the net displacement of the particle between 0 seconds and 80 seconds?
Here's the graph: http://i37.servimg.com/u/f37/16/73/53/52/graph410.png
Choices:
A. 160 meters
B. 80 meters
C. 40 meters
D. 20 meters
E. 0 meters

anonymous · Answer

Like does anyone know any equations for this?

anonymous · Answer

The displacement of any object over some interval of time is equal to the area under its velocity graph (the integral of the velocity graph) over that interval of time. 

So, lets look at the first 40 seconds. The graph forms a triangle, with the x axis being the base. So can you find the area of that triangle?
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anonymous · Answer

400 units^2?

anonymous · Answer

Remember the area of a triangle is one half its base times height. So if the base is 40, and the height is 4, what is the area? The area will be in meters. 

This area is the displacement for the first 40 seconds. Then we'll do the same thing for the last 40 seconds.

anonymous · Answer

Oh I thought you meant the area of the triangle from the graph I screenshot lol. And I see now (: Thanks

anonymous · Answer

Right. So once you do this piece, you have to do the same thing from 40 to 80, but since the graph is below the x axis, the integral is the negative area

anonymous · Answer

Oh okay~

anonymous · Answer

so what is the answer?