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Let's talk about this question.
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So on a daytona 400 auto race, a four thunderbird and the mercedes bends are moving side by side down a straightway at 71 meter per second.
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71 .5 meter per second.
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The driver of the thunderbird realizes that she must make a pit stop and she smoothly slows to a stop over a distance of, slows to a stop over a distance of 250 meters.
00:27
She spends five seconds in the pit and then accelerates our reach.
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Her previous speed of 71 .5 meter per second after a distance of 350 meters.
00:38
So at this point, how far has the thunderbird fallen behind the mercedes -benz, which has continued at the constant speed? so we need to find a total time first off, which has happened because there are, it can be broken into three parts.
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So from a to b, then from b to c, then from c to d.
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So there is an a to b to c to d.
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So from a to b, it's moving to 50 meters.
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And then this is a five second stop.
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And then it moves again to a speed of 71 .5 meter per second over here after a distance of 350 meters.
01:29
Meters and this is this is also where the speed is 71 .5 meter per second.
01:38
Alright, so the total distance which it has traveled the thunderbird has traveled is 250 plus 350.
01:50
That's pretty much clear.
01:51
So the thunderbird has started 250 plus 350 as 300, 400 and 500.
01:57
So the thunderbird has traveled a 600 meter.
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And the thunderbird is now over here.
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It's started from here.
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Now we need to find a distance which mercedes bends his travel.
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So for that, we need to find a time in this stretch.
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So let's see.
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It stops at b, so the velocity is zero.
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So what we can use is second equation of motion.
02:22
I think the second equation of motion should work.
02:28
Yes, it will.
02:29
So the second equation of motion.
02:32
Will use that s or let's call it a and let's call it in fact the s is already given that that's 250.
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So 250 is equal to initial speed which is 71 .5 times b which we have to find.
02:50
Okay now the acceleration is not given so we cannot really use this right away...