Search results
Results from the WOW.Com Content Network
The Shapiro time delay effect, or gravitational time delay effect, is one of the four classic Solar System tests of general relativity. Radar signals passing near a massive object take slightly longer to travel to a target and longer to return than they would if the mass of the object were not present.
It consists of two units with the inner unit located 10 metres (33 ft) from the runway edge. [1] The PAPI should be located on the left-hand side of the runway at right angles to the runway center line, although can be located on the right-hand side of the runway if required. The red lights are always on the side closest to the runway.
In optics, optical path length (OPL, denoted Λ in equations), also known as optical length or optical distance, is the length that light needs to travel through a vacuum to create the same phase difference as it would have when traveling through a given medium.
In general relativity, light follows the curvature of spacetime, hence when light passes around a massive object, it is bent. This means that the light from an object on the other side will be bent towards an observer's eye, just like an ordinary lens. In general relativity the path of light depends on the shape of space (i.e. the metric).
Fig. 1: Fermat's principle in the case of refraction of light at a flat surface between (say) air and water. Given an object-point A in the air, and an observation point B in the water, the refraction point P is that which minimizes the time taken by the light to travel the path APB.
A black-hole approach illusion can happen during a final approach at night (with no stars or moonlight) over water or unlit terrain to a lighted runway, in which the horizon is not visible. [4] As the name suggests, it involves an approach to landing during the night where there is nothing to see between the aircraft and the intended runway ...
A method of measuring the speed of light is to measure the time needed for light to travel to a mirror at a known distance and back. This is the working principle behind experiments by Hippolyte Fizeau and Léon Foucault. The setup as used by Fizeau consists of a beam of light directed at a mirror 8 kilometres (5 mi) away. On the way from the ...
A sideslip angle will arise if an aircraft yaws about its centre of gravity and if the aircraft sideslips bodily, i.e. the centre of gravity moves sideways. [74] These angles are important because they are the principal source of changes in the aerodynamic forces and moments applied to the aircraft.