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The Arecibo Telescope was a 305 m (1,000 ft) spherical reflector radio telescope built into a natural sinkhole at the Arecibo Observatory located near Arecibo, Puerto Rico. A cable-mount steerable receiver and several radar transmitters for emitting signals were mounted 150 m (492 ft) above the dish. Completed in November 1963, the Arecibo ...
0.8–2 MPa 120–290 psi Pressure used in boilers of steam locomotives [citation needed] 1.1 MPa 162 psi Pressure of an average human bite [citation needed] 2.8–8.3 MPa 400–1,200 psi Pressure of carbon dioxide propellant in a paintball gun [64] 5 MPa 700 psi Water pressure of the output of a coin-operated car wash spray nozzle [58] 5 MPa ...
The corresponding unit of HV is then the kilogram-force per square millimeter (kgf/mm 2) or HV number. In the above equation, F could be in N and d in mm, giving HV in the SI unit of MPa. To calculate Vickers hardness number (VHN) using SI units one needs to convert the force applied from newtons to kilogram-force by dividing by 9.806 65 ...
If Meyer's index is greater than 2.2, then the ratio increases. [1] The Brinell hardness is designated by the most commonly used test standards (ASTM E10-14 [2] and ISO 6506–1:2005) as HBW (H from hardness, B from brinell and W from the material of the indenter, tungsten (wolfram) carbide). In former standards HB or HBS were used to refer to ...
Leviathan of Parsonstown, or Rosse six-foot telescope, is a historic reflecting telescope of 72 inches (1.83 m) aperture, which was the largest telescope in the world from 1845 until the construction of the 100-inch (2.5 m) Hooker Telescope in California in 1917. The Rosse six-foot telescope was built by William Parsons, 3rd Earl of Rosse on ...
The Cassegrain reflector is a combination of a primary concave mirror and a secondary convex mirror, often used in optical telescopes and radio antennas, the main characteristic being that the optical path folds back onto itself, relative to the optical system's primary mirror entrance aperture. This design puts the focal point at a convenient ...
A Luneburg lens (original German Lüneburg lens) is a spherically symmetric gradient-index lens. A typical Luneburg lens's refractive index n decreases radially from the center to the outer surface. They can be made for use with electromagnetic radiation from visible light to radio waves. For certain index profiles, the lens will form perfect ...
Solar radiation pressure on objects near the Earth may be calculated using the Sun's irradiance at 1 AU, known as the solar constant, or G SC, whose value is set at 1361 W/m 2 as of 2011. [17] All stars have a spectral energy distribution that depends on their surface temperature. The distribution is approximately that of black-body radiation.