Stuck on simple constant accel. problem

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An antelope covers 70.0 meters in 7.00 seconds with a final speed of 15 m/s, prompting a discussion on finding its initial speed and acceleration. The relevant equations of motion for constant acceleration are provided, including formulas for velocity and distance. The user expresses difficulty in calculating the initial velocity using average velocity and the equations of motion. They mistakenly attempt to find the original velocity by taking limits, leading to incorrect results. The discussion highlights the challenge of applying the correct equations to solve for initial conditions in constant acceleration problems.
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1. An antelope moving with constant acceleration covers the distance between two points 70.0 meters apart in 7.00 seconds. It's speed as it passes the second point is 15 m/s.
A] Find speed at first point. B] What is the acceleration?




2.
From text University Physics 11th edition question 2.21 page 70
Eqns of motion with constant acceleration
Vx=Vox+AxT
X=Xo+VoxT+1/2AxT
Vx2=Vox2+2Ax(X-Xo)
X-Xo=((Vox+Vx)/2)T




3. I have tried but nothing worth posting. I'm stuck on the fact that I cannot find how to use the average Velocity to find the instantaneous Velocity at point 1, Thank you!.
 
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You know T, Vx, and (X - X0). One of the four equations will allow to to determine V0x directly.
 
Crap! For some reason I was stuck on having to find the original velocity by finding the limit as time went down to zero... So I was plugging in 0.01, 0.001 and was getting ridiculous answers. Thank you! I've posted one more problem I cannot seem to get my head around.
 
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