Most accurate relative gravimeters are " superconducting " gravimeters, and these are sensitive to one thousandth of one billionth of Earth surface gravity.
42.
Most accurate relative gravimeters are " superconducting " gravimeters, and these are sensitive to one thousandth of one billionth of Earth surface gravity.
43.
The zero-length spring is extremely important to seismometers and gravimeters because it permits the design of vertical pendulums with ( theoretically ) infinite periods.
44.
Physical scientists use gravimeters to determine the exact size and shape of the earth and they contribute to the gravity compensations applied to inertial navigation systems.
45.
The difference between clock pendulums and gravimeter pendulums is that to measure gravity, the pendulum's length as well as its period has to be measured.
46.
The constraints on temporal resolution are usually less for gravimeters, so that resolution can be increased by processing the output with a longer " time constant ".
47.
The fluctuations are measured with highly sensitive gravimeters, the effect of topography and other known factors is subtracted, and from the resulting data conclusions are drawn.
48.
The watt balance requires extremely precise measurement of the local gravitational acceleration " "'g " "'in the laboratory, using a gravimeter.
49.
During this period, LaCoste and his physics teacher Arnold Romberg invented the first modern seismographs and gravimeters, using steel and quartz ( respectively ) zero-length springs.
50.
They also invented most subsequent refinements, including the ship-mounted gravimeter, in 1965, temperature-resistant instruments for deep boreholes, and lightweight hand-carried instruments.
