
#1
Sep1213, 11:09 PM

P: 75

I know that there's 5 key equations for motion which is:
d = (vf+vi/2)t vf = vi + at d = vit + 1/2at^2 vf^2 = vi^2 + 2ad d = vft  1/2at^2 Correct? But my teacher was confusing me today and he taught us these two other equations: d = 1/2(vi+vf)t d = 1/2at^2 What are these? Are they just other "rules of motion" like everything else? 



#2
Sep1213, 11:38 PM

P: 57

The second equation 'D=1/2at^2' is one of the kinematic equations 'D=Vi+1/2at^2' where the initial velocity 'Vi' is considered to be zero.




#3
Sep1213, 11:39 PM

P: 75





#4
Sep1213, 11:52 PM

Mentor
P: 11,239

5 Kinematic Equations?Actually, only two equations are essential: v_{f} = v_{i} + at d = v_{i}t + (1/2)at^{2} The others can be derived from these two. 



#5
Sep1313, 02:57 AM

P: 49

5 eq
v final velocity u initial vel. t time s displacement a constant acc^{n} v= u +at s= ut + .5at^{2} v^{2}= u^{2} +2as s= vt  .5at^{2} s= .5(v+u)t 



#6
Sep1313, 02:59 AM

P: 49

are good adding to it this gives feel to a child what he's doing also kinematics it a beginning so one can learn these quickly as afterward formula formula formula!!! 



#7
Sep1313, 07:58 AM

P: 1,253




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