When the platform is aligned, the reflected image of the crossed hairs can be seen exactly superimposed upon the original crossed hairs.

When moving from a denser medium into a less dense one ( i. e., n < sub > 1 </ sub > > n < sub > 2 </ sub >), above an incidence angle known as the critical angle, all light is reflected and R < sub > s </ sub > = R < sub > p </ sub > = 1.

When light strikes a material, most of the light is absorbed while a smaller amount of a particular frequency or wavelength is reflected.

When the army and navy were formed, the uniforms adopted by each service reflected British military and naval tradition.

When this angle is exceeded, photons no longer penetrate the semiconductor but are instead reflected both internally inside the semiconductor crystal and externally off the surface of the crystal as if it were a mirror.

When a ray of light hits the boundary between two transparent materials, it is divided into a reflected and a refracted ray.

It is also possible to produce polarised light rays using a combination of reflection and refraction: When a refracted ray and the reflected ray form a right angle, the reflected ray has the property of " plane polarization ".

When these come into contact with an object they are usually reflected or scattered in many directions.

When a light beam crosses a boundary between materials with different kinds of refractive indices, the light beam will be partially refracted at the boundary surface, and partially reflected.

When he leaves his calling card on the windshield of David Dunn's car, he is reflected in a glass frame in his art gallery.

When a wave strikes a reflective surface, it changes direction, such that the angle made by the incident wave and line normal to the surface equals the angle made by the reflected wave and the same normal line.

When unpolarized light is incident at this angle, the light that is reflected from the surface is therefore perfectly polarized.

When light encounters a boundary between two media with different refractive indices, some of it is usually reflected as shown in the figure above.

When the wave reaches the end of the line, in general, there will be a reflected wave which travels back along the line in the opposite direction.

To see this, the three corresponding normal vectors of the corner's perpendicular sides can be considered to form a basis ( a rectangular coordinate system ) ( x, y, z ) in which to represent the direction of an arbitrary incoming ray, b, c. When the ray reflects from the first side, say x, the ray's x component, a, is reversed to-a while the y and z components are unchanged, resulting in a direction of b, c. Similarly, when reflected from side y and finally from side z, the b and c components are reversed.

When the actual transmitted ( incident ) power and the reflected power are known ( i. e., through measurements and / or calculations ), then the return loss in dB can be calculated as the difference between the incident power P < sub > i </ sub > ( in dBm ) and the reflected power P < sub > r </ sub > ( in dBm ),

When sending power down a transmission line, it is usually desirable that as much power as possible will be absorbed by the load and as little as possible will be reflected back to the source.

When the bar and resonator are properly in tune with each other, the vibrating air beneath the bar travels down the resonator and is reflected off the closure at the bottom, then returns back to the top and is reflected back by the bar, over and over, creating a much stronger standing wave and amplifying the fundamental frequency.

When he sees his own unrequited love for his parents reflected during an argument in a bar, he kills a man who serves as a proxy for his father.

When Nortel ’ s share price on the Toronto Stock Exchange began a plunge that wiped out the life savings of many investors, Roth argued that Nortel's dominance reflected a failed industrial policy that sheltered enterprises from global competition.

When looking for a long-term partner more conventional altruism may be preferred which may indicate that he is also willing to share resources with her and her children while when looking for a short-term partner heroic risk-taking, which may be costly signal showing good genes, may be more preferable.

When the Israelites, led by Joshua toward the Promised Land, arrived at the banks of the River Jordan, the Ark was carried in the lead preceding the people and was the signal for their advance ( Joshua 3: 3, 6 ).

When compressed, the crystal produces a small electrical current, so when placed under the bridge saddle, the vibrations of the strings through the saddle, and of the body of the instrument, are converted to a weak electrical signal.

When analog television was developed, no affordable technology for storing any video signals existed ; the luminance signal has to be generated and transmitted at the same time at which it is displayed on the CRT.

When gastric hydrochloric acid reaches the nerves in the gastrointestinal mucosa, they signal pain to the central nervous system.

When the signal drive to the amplifier is increased, the output also increases until a point is reached where some part of the amplifier becomes saturated and cannot produce any more output ; this is called clipping, and results in distortion.

When conjugation is initiated by a signal the relaxase enzyme creates a nick in one of the strands of the conjugative plasmid at the oriT.

When the Laplace transform is performed on a discrete-time signal ( with each element of the discrete-time sequence attached to a correspondingly delayed unit impulse ), the result is precisely the Z transform of the discrete-time sequence with the substitution of

When the key was not in use, that switch was kept closed, so that a signal was continually sent.

When she was half a mile away, Baralong ran up a signal flag indicating that she was going to rescue Nicosians crew.

When Datis surrendered and was ready for retreat, the Ionians climbed the trees and gave the Athenians the signal that the cavalry had left.

When the Athenian line was ready, according to one source, the simple signal to advance was given by Miltiades: " At them ".

When the trumpet signal for the start rang out, Antony's fleet began issuing from the straits, and the ships moved into line and remained quiet.

When the infant BBC Television service was started in 1936, Rediffusion, which had supplied cable radio services since 1928, started providing " Pipe TV " to its customers who had difficulties tuning into the weak TV broadcast signal.

When the bridge was in use, boaters would signal the operator, who would start a diesel engine and rotate the bridge to the open position on a large gear.

When the keyboard processor detects that a key has changed state, it sends a signal to the CPU indicating the scan code of the key and its new state.

When Greek orthography was codified by grammarians in the Hellenistic era, they used a diacritic symbol derived from this half-H shape to signal the presence of / h /, and added as its counterpart a reverse-shaped diacritic to denote absence of / h /.

When the power supply to the amplifier is first switched on, electronic noise in the circuit provides a signal to get oscillations started.

When such a system is subject to an impulse ( or any signal of finite duration ) it will respond with an output waveform which lasts past the duration of the input, eventually decaying exponentially in one or another manner, but never completely settling to zero ( mathematically speaking ).

When a pedal is off or inactive, the electric audio signal coming in to the pedal is diverted onto a " bypass ", resulting in a " dry " signal which continues on to other effects down the chain.

When a pilot moves the control column ( or sidestick ), a signal is sent to a computer ( analogous to moving a game controller ) the signal is sent through multiple wires ( channels ) to ensure that the signal reaches the computer.

When it appeared that the revolt would succeed, the Thrintun elders built and used a psychic amplifier that forced every sentient being in the galaxy to commit suicide, the signal repeating for centuries.