I'm struggling on manipulating kinematics

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The discussion focuses on deriving an expression for velocity (v) that does not explicitly depend on time using the kinematic equations. Participants clarify the correct forms of the equations, emphasizing the need to manipulate them accurately. One user suggests expressing time (t) in terms of velocity and substituting it into the position equation. Another contributor confirms that using the equation v² = u² + 2as leads to the desired result. The conversation highlights the importance of careful algebraic manipulation in solving kinematic problems.
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Homework Statement


Given the equations X=X0+v0t+1/2at^2 and v=v0t+at, show that an expression for v that has no explicit dependence on time can be written as v=+-√v0^2+2a(X-X0)

Homework Equations

The Attempt at a Solution


I thought I would manipulate the first given equation to be X-X0/t = [1/2(v-v0)] but as I got to the end it didn't work. Please help.
 
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Rebecca Berger said:

Homework Statement


Given the equations X=X0+v0t+1/2at^2 and v=v0t+at, show that an expression for v that has no explicit dependence on time can be written as v=+-√v0^2+2a(X-X0)

Homework Equations

The Attempt at a Solution


I thought I would manipulate the first given equation to be X-X0/t = [1/2(v-v0)] but as I got to the end it didn't work. Please help.
Welcome to the PF.

Please show us in detail your work. We can try to help if you show your work to us. :smile:
 
Rebecca Berger said:
v=v0t+at,
Shouldn't this be v=v0+at?
I believe taking square on both the sides of this equation would help.
 
I took X=X0+v0t+1/2at^2 and separated v0t because v=v0+at so it can just say vt . I then subtracted X0 from both sides and divided by t on both sides. My final equation was X-X0/t=[1/2(v+v0)]
 
cnh1995 said:
Shouldn't this be v=v0+at?
I believe taking square on both the sides of this equation would help.
Yes, sorry I made a typo
 
Rebecca Berger said:
I took X=X0+v0t+1/2at^2 and separated v0t because v=v0+at so it can just say vt . I then subtracted X0 from both sides and divided by t on both sides. My final equation was X-X0/t=[1/2(v+v0)]
I manipulated the wrong equation
 
the standard notation is v=u+at and s=ut+1/2*a*t2. Express t=(v-u)/a, substitute in s eqn, simplify and you get the answer. v2-u2=2as.
 

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