Impulse Graph

[princesslinda]

This question is from EK 1001 #426 and requires the graph given.

The question is: Which of the following statements is true if the mass is at rest at t=0?
(a) The velocity of the mass is decreasing between 10 and 20 secs
(b) The acceleration of the mass is constant between 0 and 10 secs
(c) At, 40 secs, the mass is stationary.
(d) The distance traveled by the mass between 0 and 10 secs is equal to the distance traveled by the mass between 10 and 20 secs

The answer EK gives is (c), and they state that (d) is incorrect because the smallest velocity between 10s and 20s is greater than the greatest velocity between 0s and 10s.

My question is in regards to the last part of the answer. How do you find the velocity in the graph (as I am having trouble seeing the velocity differences in the graph and don't know what they are referring to)?

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[Morsetlis]

Maybe you could... draw or upload the graph?...

Impulse = Momentum

Ft = mv

 

[azerkail]

if velocity is distance / time and the graph has distance on the y axis and time on the x, velocity would be the slope of the line.

if graph is given as velocity vs time then a sloped line gives velocity / time. accerlation is found by the slope of the line. flat horizontal lines parallel to x axis imply constant velocity (acceleration is 0). vertical lines parallel to y axis imply instantaneous acceleration (this is probably not the case)

OP, we need to see this graph.

 

[Erythropoietin]

You can view that graph as acceleration vs time graph, since force and acceleration are proportional.
Velocity will be the area under the line. But I also get d) as an answer choice.
It's saying that mass is stationary at t = 40 s, but we are not sure whether if acceleration is zero at that point or if the object is moving at a constant velocity.
So I'm not really sure but that's how I thought about it.