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3-8. When performing measurements above 1
GHz in a flow calorimeter, which of the
following dielectrics do you normally
use?
1. Water
2. Oil
3. MEK
4. H2SO4
3-9. Which of the following government
agencies is/are responsible for
maintaining our primary?
1. U. S. National Bureau of Standards
2. U. S. Naval Observatory
3. Department of Weights and Measures
4. All of the above
3-10. When using a stroboscope to measure an
unknown frequency, which, if any, of the
following steps should you take?
1. Start the measurement at the lowest
frequency that the stroboscope can
deliver and increase the flashing rate
until a single image is obtained
2. Start the measurement at the highest
frequency that the stroboscope can
deliver and reduce the flashing rate
until a single stationary image is
obtained
3. Start the measurement at the midscale
range of the stroboscope and adjust
the flashing rate, in either direction,
until a harmonic of the primary
frequency is obtained
4. None of the above
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INTENTIONALLY.
3-11. If you anticipate using a stroboscope
over an extended period of time, which
of the following actions can you take to
extend flasher-tube life?
1. Operate the stroboscope at a
submultiple of the fundamental
synchronous speed
2. Lower the plate voltage of the flasher
tube
3. Lower the filament voltage of the
flasher tube
4. Operate the stroboscope at a multiple
of the fundamental synchronous
speed
3-12. Vibrating reed meters and moving disk
meters are primarily used to measure
which of the following values?
1. The frequency of 60-Hz ac power
2. The rotational speed of synchronous
motors
3. Frequencies between 1 kHz and 10
MHz
4. The frequencies of multiplexed
signals
3-13. When using an oscilloscope to measure
frequencies, which of the following
formulas should you use?
1.
2.
3.
4.
