الفيزياء العامة الجزء الثاني#موقع الفيزياء.كوم

Appendices
Cathode Ray Oscilloscope
جھاز راسم الذبذبات الكھربائية
OSCILLOSCOPE, electronic instrument that records changes in the
voltage of an electric or electronic circuit by a trace of light on the face of a
cathode-ray tube (CRT). Oscilloscopes are widely used throughout industry
and in scientific laboratories to test and adjust electronic equipment and to
follow extremely rapid oscillations in electric voltages; the oscilloscope is
capable of following changes that occur within several billionths of a
second. Special converters attached to an oscilloscope can convert
mechanical vibrations, sound waves, and other forms of oscillatory motion
into electrical impulses that can be observed on the face of the CRT.
Oscilloscopes measure 2 things: voltage and time (and with time, often,
frequency). An electron beam is swept across a phosphorescent screen
horizontally (X direction) at a known rate (say 1 sweep in a millisecond).
An input signal is used to change the position of the beam in the Y
direction. The trace left behind can be used to measure the voltage of the
input signal (off the Y axis) and the duration or frequency can be read off
the X axis.
تنبعث الإلكترونات من الفتيلة بواسطة التسخين.‏
فرق جهد بناء على العلاقة التالية
ثم تعجل هذه الإلكترونات في اتجاه الانود بواسطة
1
2
2
mv qV
حيث أن
q شحنة الإلكترون وV فرق الجهد بين الكاثود والانود.‏
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