Engineering Mechanics: car speeding up

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Joe_1234
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A car starting from rest picks up at a uniform rate and passes three electric post in succession. The post are spaced 360 m apart along a straight rod. The car takes 10 seconds to travel from the first post to the 2nd post and tales 6 seconds to go from the 2nd post to the 3rd post. Determine the distance from the starting point to the first post.
 
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let $d$ be the distance from the starting point to the first post, $t$ be the time it takes to reach the first post from rest, and $a$ be the magnitude of the uniform acceleration.

$d = \dfrac{1}{2}at^2$

$d+360 = \dfrac{1}{2}a(t+10)^2$

$d+720 = \dfrac{1}{2}a(t+16)^2$

solve the system for $d$
 
skeeter said:
let $d$ be the distance from the starting point to the first post, $t$ be the time it takes to reach the first post from rest, and $a$ be the magnitude of the uniform acceleration.

$d = \dfrac{1}{2}at^2$

$d+360 = \dfrac{1}{2}a(t+10)^2$

$d+720 = \dfrac{1}{2}a(t+16)^2$

solve the system for $d$
Thank you