How Far Was the Turtle from the Fence Post at the Start?

[tiffanyg]

a turtle is moving with a constant acceleration along a straight ditch. He starts a stopwatch as the turtle passes a fence post and notes that it takes him 10s to reach a pine tree 10m farther along a ditch. as the turtle passes the pine tree, his speed is 1.2m/s.

how far was he from the fence post when he started from rest??

 

[logickills]

Attempt this at least. If you have to draw a diagram. Once I see that you have at least tried I can give you a hand.

 

[tiffanyg]

i did try it,but i don't know it what i did is right, because i let 1.2 be the final velocity of the segment of motion where time and displacement is given, to find acceleration. But i don't know if what i did is right... =[

 

[logickills]

Ok the first thing you need to do is to identify all the variables you know and you don't know. Once you do that you can narrow down the equations you can use.

 

[tiffanyg]

ok, so first: i did a diagram divided into 3 sec:
1- when the turtle is going at constant acceleration (only initial velocity is given = 0)
2- when he gets to the fence (where time and displacement is given t=10 , d=10)
3- where he passes the tree (only velocity = 1.2m/s) is given =]

in section 1- i don't have acceleration and displ.
2- no velocity
3- no acceleration, and displacement

 

[tiffanyg]

since i have velocity in sec3, i can used it as vf for section 2..is that right?