displacement how close particle get to A please help

Just need help with part iii please help

how can you find distance from a vel-time graph?

how can you find distance from a vel-time graph?

you find the area from the graph to the x axis

OK so you know where it is after 4 secs then what happens?

the particle then goes the opposite way

Yes, so when it is nearest A?

Displacement is the distance from the starting point.

• Work out the area under the line when the particle is moving forwards (above x axis)
• Work out the area above the line when the particle is moving backward (below x axis)
• Take away the second answer from your first answer and you have the displacement.

Thanks but isn't what you advised above finding the displacement from A after 9 seconds?
How is this the same thing as what the question is asking "When t=0 the particle is at A. Calculate how close the particle gets to A during the interval 4≤ t ≤12 " This interval bit that theyve added to the question has really messed up with my understanding of what the question wants you to do.

thanks so i got 7.5 but the wording of the question is confusing me what do they mean by the during the interval 4≤ t ≤12 bit? I don't understand how what we did here is related to the question? Like what is the question asking?

I see what you mean, however read this.
You have to find the closest the particle gets to A, this is when it has moved as far back as possible. When velocity is negative it is moving backwards. It gets closest to A when it has finished moving backwards which is at 9 seconds.

If they didn't specify the interval, you could just say "it starts at A (when t = 0), so the closest it gets to A is 0m". Since they don't want you to do that, they set an interval.

ooooooh thanks! I get it

No worries, I didn’t read the question properly. Don’t add the area of the forwards movement at the end because it’s after.