speed time graphh expertsssssss

Problem Solving — algebra and arithmetic (GMAT Focus Edition)
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speed time graphh expertsssssss

by marmar29 » Tue Feb 22, 2011 2:10 am
hi all
im stuck with how to find the acceleration in the sp-time graph! & the deacceleration
i need an easy way to solve it
here is a picture attached
where the x-axis is the "t" & its divide into 5 ,15 ,30 ( not divide into smaller number inbetween so u cant knw where 10 lay ) & y axis is" v"& only has 30 on the same line of the constant velocity )

now the question is find the acc. whn t =20 !!!
show me the rule used or the steps
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travelgraph2.gif
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by BarryLi » Tue Feb 22, 2011 2:22 am
The way I approached the question was recalling that acceleration is the measure of change in velocity with respect to time (velocity divided by time). Since the graph has time on the x-axis and velocity on the y-axis, the slope of the line is equal to the acceleration at any point on the line.

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by gmatpill » Fri Feb 25, 2011 1:50 pm
marmar29 wrote:hi all
im stuck with how to find the acceleration in the sp-time graph! & the deacceleration
i need an easy way to solve it
here is a picture attached
where the x-axis is the "t" & its divide into 5 ,15 ,30 ( not divide into smaller number inbetween so u cant knw where 10 lay ) & y axis is" v"& only has 30 on the same line of the constant velocity )

now the question is find the acc. whn t =20 !!!
show me the rule used or the steps

When t=20, you are right on the flat part of the graph. Acceleration measures the change in velocity with respect to time. Velocity is not changing at this time, it stays the same! Flat! The slope of velocity (ie acceleration) is zero!

Zero acceleration!