Simple "Mass on Spring" Simulation

This code simulates oscillation of mass on a spring and graphs that motion. To use this code, just start a new project, place a picture box on the form, paste the code into the form's Load event, and run the program.

Code:

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'set up the display------------------------------
Form1.ScaleMode = 3
With Picture1
.Appearance = 0
.BorderStyle = 0
.AutoRedraw = True
.Width = 257
.Height = 257
.ScaleMode = 0
.ScaleWidth = .Width
.ScaleHeight = -.Height
.ScaleLeft = 0
.ScaleTop = .Height \ 2
End With

'run the simulation------------------------------
Dim f As Double 'net force acting on mass
Dim a As Double 'acceleration
Dim v As Double 'velocity
Dim p As Double 'position
Dim k As Double 'spring constant
Dim d As Double 'damping factor
Dim m As Double 'mass
Dim i As Double 'time increment
Dim t As Double 'time

p = 100
k = 0.1
d = 0.15
m = 2
i = 0.01

For t = 0 To 257 Step i
f = (-p * k) + (-v * d)
a = f / m
v = v + a * i
p = p + v * i
Picture1.PSet (t, p)
Next t

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