Grass cutting rates will also vary depending on the frequency of mowing. If you have your lawn trimmed too infrequently, it will be more difficult to maintain. They are also based on square footage, though there is a minimum cost.rass cutting rates will also vary depending on the frequency of mowing. If you have your lawn trimmed too infrequently, it will be more difficult to maintain. They are also based on square footage, though there is a minimum cost.
A tonometer is a tool used to check the pressure exerted by the fluid inside a person's eyes in terms of millimeters of mercury (mmHg). This is done to make sure the eyes and optic nerves are healthy.
Anemometer: Anemometer, device for measuring the speed of airflow in the atmosphere, in wind tunnels, and in other gas-flow applications. Most widely used for wind-speed measurements is the revolving-cup electric anemometer, in which the revolving cups drive an electric generator. The output of the generator operates an electric meter that is calibrated in wind speed. The useful range of this device is approximately from 5 to 100 knots. A propeller may also be used to drive the electric generator, as in the propeller anemometer. In another type of wind-driven unit, revolving vanes operate a counter, the revolutions being timed by a stopwatch and converted to airspeed.