Write briefly about (a) Shock Waves (b) Sound Barrier (c) Solar Cell (d) Super Fluid (e) Tsunami (f) Photovoltaic Cell (g) Hygrometer

Write briefly about
(a) Shock Waves
(b) Sound Barrier
(c) Solar Cell
(d) Super Fluid
(e) Tsunami
(f) Photovoltaic Cell
(g) Hygrometer
by

1 Answer

Answer :

(a) Shock Waves
In fluid dynamics, a shock wave is a nonlinear or discontinuous pressure wave. It can also be when the actual molecular or particle speed is moving faster than the wave propagation speed  (space shuttle through air). They can and do transport and transmit tremendous amounts of energy (hundreds of Megawatts per square meter for shocks generated by nuclear explosions).

(b) Sound Barrier
In aerodynamics, the sound barrier is the apparent physical boundary stopping large objects from becoming supersonic. The term came into use during World War II when a number of aircraft started to encounter the effects of compressibility, a grab-bag of unrelated aerodynamic effects, and fell out of use in the 1950s when aircraft started to routinely "break" the sound barrier.

(c) Solar Cell
A solar cell, or photovoltaic cell, is a semiconductor device consisting of a large-area p-n junction diode, which, in the presence of sunlight is capable of generating usable electrical energy. This conversion is called the photovoltaic effect. The field of research related to solar cells is known as photovoltaic.

(d) Super Fluid
Super fluidity is a phase of matter characterized by the complete absence of viscosity. Thus super fluids, placed in a closed loop, can flow endlessly without friction. Super fluidity was discovered by Pyotr Leonidovich Kapitsa, John F. Allen, and Don Misener in 1937. The study of super fluidity is called quantum hydrodynamics.

(e) Tsunami
Tsunami is a natural phenomenon consisting of a series of waves generated when water in a lake or the sea is rapidly displaced on a massive scale. Earthquakes, landslides, volcanic eruptions and large meteorite impacts all have the potential to generate a tsunami. The effects of a tsunami can range from unnoticeable to devastating.

(f) Photovoltaic Cell
Same As Solar Cell.

(g) Hygrometer
Hygrometers are instruments used for measuring humidity. The simplest form of a hygrometer consists of two thermometers, one of which has its bulb constantly kept wet. Evaporation from the bulb lowers the temperature so that this thermometer usually shows a lower temperature.
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