Question

What are equations of motion?

Answer 1

There are three equations of motion :

1).   v = u + at

2). s = ut + 1/2 at²

3).  2as = v² - u²

Answer 2

u----initial velocity
v---final velocity
a--- acceleration
g--acceleration due to gravity
s-- distance tralelled
t--- time taken
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the basic equations of motion are
1) v = u +at
2)s = ut + 1/2at²
3)v²= u² + 2as
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CASE 1
Body undergoing retardation:
v= u - at
s= ut - 1/2at²
v²= u² - 2as
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Case 2
body is falling freely
the gravity will be acting down wards and the body is also falling down so the gravity will  be taken as positive
v= u + gt
s= ut + 1/2gt²
v²= u² + 2gs
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CASE 3 
body thrown upwards
the gravity will be acting downwards so the value of 'g' is taken as negative
v= u - gt
s= ut - 1/2gt²
v²= u² - 2gs
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stopping distance =   u²  
                                     a
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distance traveled by the body in nth second
Sn = u + a/2  (2n-1)
 Sn -- Distance traveled in nth second
u = initial velocity
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speed = distance / time
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velocity = displacement /time
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acceleration = velocity /time
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centripetal acceleration = ω² r
r-- radius
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centripetal fore = mω²r
m-- mass
r- radius
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where ω = v²/r for both the centripetal formulas given above
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