Deriving kinematic equations from average velocity and acceleration

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Homework Statement


Derive the kinematic equations for constant a from change in x=V(avg)Xt & change in v= a(avg)Xt


Homework Equations


v=v(o)+at
(Every other equation that can be made from x=x(1)+V(0)t+.5at^2)
x= position
a=acceleration (constant)
v=velocity
t=time


The Attempt at a Solution


My main problem with this problem is that I don't know exactly what it's asking and the phrasing confuses me.
But what I did was turned the change in x=V(avg)Xt into v=v(o)+at through deriving and substitution.
For the change in v= a(avg)Xt equation, I turned it into a=change in v/t through deriving and substitution.
Once again I'm not even sure that I even answered the question, can someone please interpret the question in a way I can understand it?
Thanks in advance.
 
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hi max

since the acceleration is constant, [tex]\inline{a_{avg}=constant=a}[/tex]
and the equations you are supposed to use are [tex]\inline{x=V_{avg}t}[/tex] and
[tex]\text{change in v}=a_{avg}t=at[/tex]

now remember that

[tex]V_{avg}=\frac{V+V_o}{2}[/tex]

and change in V=final velocity - initial velocity = [itex]V-V_o[/itex]

so use these equations , manipulate them...

for example... [itex]\text{change in v}=V-V_o = at[/itex]
so [itex]V=V_o +at[/itex] this would be one of the equations of kinematics for the constant
acceleration..
 
Last edited:
Hi Issac, I know how to manipulate the equations and such, my main problem is that I don't know what the question itself is asking. Like am I supposed to find a= through the 2 equations?
 
there are 3 main equations of the kinematics for the constant acceleration ... i already showed you one of them...now to get the second equation, you need to eliminate V and get an equation in x, V_o ,a and t... do it