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Answer:Heinrich Rudolf Hertz's birthday ..He (February 22, 1857 – January 1, 1894) was a German physicist who clarified and expanded the electromagnetic theory of light that had been put forth by Maxwell. He was the first to conclusively prove the existence of electromagnetic waves by engineering instruments to transmit and receive radio pulses using experimental proceduresthat ruled out all other known wireless phenomena.
Electromagnetic research
In 1886, Hertz developed the Hertz antenna receiver. This is a set of terminals which is not electrically grounded for its operation. He also developed a transmitting type of dipole antenna, which was a center-fed driven element for transmitting UHF radio waves. These antennas are the simplest practical antennas from a theoretical point of view.
In 1887, Hertz experimented with radio waves in his laboratory. These actions followed Michelson's1881 experiment (precursor to the 1887 Michelson-Morley experiment) which did not detect the existence of aether drift, Hertz altered the Maxwell's equations to take this view into account for electromagnetism. Hertz used a Ruhmkorff coil-driven spark gap and one meter wire pair as a radiator. Capacity spheres were present at the ends for circuit resonance adjustments. His receiver, a precursor to the dipole antenna, was a simple half-wave dipole antenna for shortwaves. Hertz published his work in a book titled: Electric waves: being researches on the propagation of electric action with finite velocity through space.
Through experimentation, he proved that transverse free space electromagnetic waves can travel over some distance. This had been predicted by James Clerk Maxwell and Michael Faraday. With his apparatus configuration, the electric and magnetic fields would radiate away from the wires as transverse waves. Hertz had positioned the oscillator about 12 meters from a zinc reflecting plate to produce standing waves. Each wave was about 4 meters. Using the ring detector, he recorded how the magnitude and wave's component direction vary. Hertz measured Maxwell's waves and demonstrated that the velocity of radio waves was equal to the velocity of light. The electric field intensity and polarity was also measured by Hertz. (Hertz, 1887, 1888).
The Hertzian cone was first described by Hertz as a type of wave-front propagation through variousmedia. His experiments expanded the field of electromagnetic transmission and his apparatus was developed further by others in the radio. Hertz also found that radio waves could be transmitted through different types of materials, and were reflected by others, leading in the distant future toradar.
Hertz helped establish the photoelectric effect (which was later explained by Albert Einstein) when he noticed that a charged object loses its charge more readily when illuminated by ultraviolet light. In 1887, he made observations of the photoelectric effect and of the production and reception of electromagnetic (EM) waves, published in the journal Annalen der Physik. His receiver consisted of a coil with a spark gap, whereupon a spark would be seen upon detection of EM waves. He placed the apparatus in a darkened box to see the spark better. He observed that the maximum spark length was reduced when in the box. A glass panel placed between the source of EM waves and the receiver absorbed ultraviolet radiation that assisted the electrons in jumping across the gap.
When removed, the spark length would increase. He observed no decrease in spark length when he substituted quartz for glass, asquartz does not absorb UV radiation. Hertz concluded his months of investigation and reported the results obtained. He did not further pursue investigation of this effect, nor did he make any attempt at explaining how the observed phenomenon was brought about.
Hertz did not realize the practical importance of his experiments. He stated that,
- "It's of no use whatsoever[...] this is just an experiment that proves Maestro Maxwell was right — we just have these mysterious electromagnetic waves that we cannot see with the naked eye. But they are there."[5][dead link]
Asked about the ramifications of his discoveries, Hertz replied,
- "Nothing, I guess."
His discoveries would later be more fully understood by others and be part of the new "wireless age". In bulk, Hertz' experiments explain reflection, refraction, polarization, interference, and velocityof electric waves.
In 1892, Hertz began experimenting and demonstrated that cathode rays could penetrate very thin metal foil (such as aluminium). Philipp Lenard, a student of Heinrich Hertz, further researched this "ray effect". He developed a version of the cathode tube and studied the penetration by X-rays of various materials. Philipp Lenard, though, did not realize that he was producing X-rays. Hermann von Helmholtz formulated mathematical equations for X-rays. He postulated a dispersion theory before Röntgen made his discovery and announcement. It was formed on the basis of the electromagnetic theory of light (Wiedmann's Annalen, Vol. XLVIII). However, he did not work with actual X-rays.
Death at age 36
In 1892, an infection was diagnosed (after a bout of severe migraines) and Hertz underwent some operations to correct the illness. He died of Wegener's granulomatosis at the age of 36 in Bonn, Germany in 1894, and was buried in Ohlsdorf, Hamburg at the Jewish cemetery.[6]
Hertz's wife, Elizabeth Hertz (maiden name: Elizabeth Doll), did not remarry. Heinrich Hertz left two daughters, Joanna and Mathilde. Subsequently, all three women left Germany in the 1930s and went to England, after the rise of Adolf Hitler. Charles Susskind interviewed Mathilde Hertz in the 1960s and he later published a book on Heinrich Hertz. Heinrich Hertz's daughters never married and he does not have any descendants, according to the book by Susskind.
Legacy and honors
His nephew Gustav Ludwig Hertz was a Nobel Prize winner, and Gustav's son Carl Hellmuth Hertzinvented medical ultrasonography.
The SI unit hertz (Hz) was established in his honor by the IEC in 1930 for frequency, a measurement of the number of times that a repeated event occurs per second (also called "cycles per sec" (cps)). It was adopted by the CGPM (Conférence générale des poids et mesures) in 1964.
In 1969 (East Germany), a Heinrich Hertz memorial medal was cast. The IEEE Heinrich Hertz Medal, established in 1987, is "for outstanding achievements in Hertzian waves [...] presented annually to an individual for achievements which are theoretical or experimental in nature".
A crater that lies on the far side of the Moon, just behind the eastern limb, is named in his honor. The Hertz market for radioelectronics products in Nizhny Novgorod, Russia, is named after him. The Heinrich-Hertz-Turmradio telecommunication tower in Hamburg is named after the city's famous son.
Hertz is honored by Japan with a membership in theOrder of the Sacred Treasure, which has multiple layers of honor for prominent people, including scientists.[7]
Heinrich Hertz has been honored by a number of countries around the world in their postage issues, and in post-World War II times has appeared on various German stamp issues as well.
On his birthday today , Google honored Hertz with a Google doodle inspired by his life's work, on their home page.You have already watched the doodle on the top of this article ,this is google's 1308 th doodle on its home page since the first ever Google doodle back on August 30, 1998.
OPEN THE LINK BELOW AND SEE ALL THE DOODLES
OPEN THE LINK BELOW AND SEE ALL THE DOODLES
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