# Calculating Normal Force

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I'm trying to create a function that calculates the normal force of an object, and was wondering if my code is right or not?

Private Sub Physics_Normal_Force(m As Single, g As Single, Angle As Single, N As Point_2D)

N.X = m * g * Cos(Angle * PI / 180)
N.Y = m * g * Sin(Angle * PI / 180)

End Sub



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From what you posted it seems correct. But without any other context there's no way for us to tell for sure [smile]

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Well I wasn't too sure if it was correct cause if the angle is 0, then N.Y = 0 and N.X was not 0, which didn't make any sense. If I reversed the cos and sin's around, then it sorta would make sense.

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Fx = mg * sin ( angle )
Fy = mg * cos ( angle )
Rn= Fy
Ft = Cf * Rn = Cf * Fy = Cf * mg * cos ( angle )
Fx -Ft = m * a
a= ( Fx-Ft ) / m
s= 0.5 *a *t*t +v0 *t + s0
ds/dt = v = a* t+ v0
ds2/dt2 = dv/dt = a

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Quote:
 Original post by Jacob RomanWell I wasn't too sure if it was correct cause if the angle is 0, then N.Y = 0 and N.X was not 0, which didn't make any sense. If I reversed the cos and sin's around, then it sorta would make sense.

In that case it depends what you consider 0°. If 0° is when the ground is facing up and N.X is to the right then your results would seem weird. However let's say you consider a flat ground 90°, or in other words use the direction of the normal as the orientation of the ground. Then the results would make more sense. Since sine and cosine are 90° out-of-phase, it explains why you would think of switching them.

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Ohhhhh, yeah ok. I think that's why now. Thanks. ;)

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