File:VFPt capacitor-square-plate.svg
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Size of this PNG preview of this SVG file: 800 × 600 pixels. Other resolutions: 320 × 240 pixels | 640 × 480 pixels | 1,024 × 768 pixels | 1,280 × 960 pixels | 2,560 × 1,920 pixels.
Original file (SVG file, nominally 800 × 600 pixels, file size: 27 KB)
Summary
| Description |
English: Accurately computed electric field of simple parallel plate capacitor. The capacitor consists of two square plates with plate size a and distance d=a/3. The field is accurately computed for a uniform charge distribution on each plate, but therefore the potential on each plate is not exactly constant. |
| Date | |
| Source | Own work |
| Author | Geek3 |
| Other versions |
Slightly different field configurations:
|
| SVG development |  This plot was created with VectorFieldPlot. |
| Source code | Python code# paste this code at the end of VectorFieldPlot 2.0
doc = FieldplotDocument('VFPt_capacitor-square-plate', width=800, height=600, commons=True)
l = 4.5
d = 1.5
plates = [{'x0':-l/2., 'y0':d/2., 'x1':l/2., 'y1':d/2., 'Lz':l, 'Q':1.},
{'x0':-l/2., 'y0':-d/2., 'x1':l/2., 'y1':-d/2., 'Lz':l, 'Q':-1.}]
field = Field([['charged_rect', plates[0]], ['charged_rect', plates[1]]])
def startpath(t):
# take an oval with stright lines and half-cirles around one plate
tt = (t%1) * (2 * l + pi * d)
if tt <= l*0.5:
return sc.array([tt, d])
elif tt <= l*0.5 + pi/2.*d:
phi = (tt - l*0.5) / (d/2.)
return sc.array([l*0.5 + d*0.5*sin(phi), d*0.5 + d*0.5*cos(phi)])
elif tt <= l*1.5 + pi/2.*d:
return sc.array([l - (tt - pi/2.*d), 0.])
elif tt <= l*1.5 + pi*d:
phi = (tt - l*1.5) / (d/2.)
return sc.array([-l*0.5 + d*0.5*sin(phi), d*0.5 + d*0.5*cos(phi)])
else:
return sc.array([tt - (l*2. + pi*d), d])
nlines = 22
p0list = Startpath(field, startpath).npoints(nlines)
# plot field lines
for p0 in p0list:
line = FieldLine(field, p0, directions='both')
doc.draw_line(line, arrows_style={'dist':2, 'min_arrows':1})
# plot capacitor plates
D = 0.055
lw = 0.01
nsign = nlines
plus = 'M 0,-0.02 v 0.04 M -0.02,0 h 0.04'
minus = 'M -0.02,0 h 0.04'
for p in plates:
M = 0.5 * (sc.array([p['x0'], p['y0']]) + sc.array([p['x1'], p['y1']]))
R = sc.array([p['x1'], p['y1']]) - M
a = atan2(R[1], R[0])
if p['Q'] > 0:
col = '#e22'
sign = plus
else:
col = '#45e'
sign = minus
transform = 'translate({:.6g},{:.6g})'.format(M[0], M[1])
transform += ' rotate({:.6g})'.format(degrees(a))
doc.draw_object('rect', {'x':-vabs(R)-lw/2., 'width':2*vabs(R)+lw,
'y':-D, 'height':2*D,
'style':'fill:{:s}; stroke:#000; stroke-width:{:.6g}'.format(col, lw),
'transform':transform})
for i in range(nsign):
pos = M + R * (2 * (i + 0.5) / nsign - 1)
doc.draw_object('path', {'d':sign,
'transform':'translate({:.6g},{:.6g})'.format(*pos),
'style':'fill:none; stroke:#000; stroke-width:{:.6g}; '.format(2*lw) +
'stroke-linecap:square'})
doc.write()
|
Licensing
I, the copyright holder of this work, hereby publish it under the following license:
This file is licensed under the Creative Commons Attribution-Share Alike 4.0 International license.
- You are free:
- to share – to copy, distribute and transmit the work
- to remix – to adapt the work
- Under the following conditions:
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File history
Click on a date/time to view the file as it appeared at that time.
| Date/Time | Thumbnail | Dimensions | User | Comment | |
|---|---|---|---|---|---|
| current | 22:50, 7 September 2019 | | 800 × 600 (27 KB) | wikimediacommons>Geek3 | User created page with UploadWizard |
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