RRB NTPC GK Questions 2026

John Bardeen, Walter Brattain and William Shockley built the first working transistor at Bell Laboratories in the United States in 1947, and the three shared the Nobel Prize in Physics in 1956 for the discovery of the transistor effect; the device replaced the bulky vacuum tube and made all later…

A trivalent dopant such as boron, aluminium, gallium or indium forms only three covalent bonds with the surrounding silicon atoms, leaving one bond incomplete; that vacancy behaves as a mobile positive carrier called a hole, and holes therefore become the majority carriers while thermally generated electrons remain the minority carriers.

Silicon has four valence electrons, so adding a pentavalent atom such as phosphorus, arsenic, antimony or bismuth leaves one electron over after four bonds are formed; that spare electron is loosely held and becomes a free carrier, making electrons the majority carriers and the crystal n-type.

In an intrinsic, that is a chemically pure, semiconductor every free electron is produced by breaking a covalent bond, and breaking a bond leaves behind exactly one hole, so electrons and holes are created strictly in pairs and their concentrations must be equal.

The energy gap between the valence band and the conduction band decides whether a solid conducts: in silicon the gap is roughly 1.1 electron volts, small enough for heat or light to lift some electrons across it, which is what makes silicon a semiconductor.

Jharkhand is bounded by Bihar to the north, West Bengal to the east, Odisha to the south, Chhattisgarh to the west and Uttar Pradesh to the north-west, so it touches five states, and Madhya Pradesh is not among them.

The Jaduguda mine in the Singhbhum belt began operating in the late nineteen sixties and is India's first and best known uranium mine, worked by the Uranium Corporation of India Limited, whose headquarters is also in the district; the same belt holds the copper mines around Ghatsila and Mosaboni.

Seraikela, in the Seraikela Kharsawan district, gives its name to one of the three recognised styles of Chhau, a masked dance drama inscribed on the UNESCO list of the intangible cultural heritage of humanity in 2010; the other two styles are Mayurbhanj in Odisha, which is danced without masks, and…

Sarhul marks the new year for many tribal communities of the Chhotanagpur plateau and is celebrated when the sal tree comes into flower in spring; the village priest offers the first sal blossoms, and only after the festival may the new flowers and fruit of the season be used.

The Damodar Valley Corporation was created by an Act of Parliament in 1948 as independent India's first multipurpose river valley project, built on the American Tennessee Valley Authority model to control the floods of the Damodar, generate power and supply water across what is now Jharkhand and West Bengal; its…

Betla National Park lies in the Latehar district on the Chhotanagpur plateau and forms the core of the Palamu Tiger Reserve, which was among the first group of tiger reserves notified when Project Tiger was launched in 1973 and is often cited as the place where an early census of…

The Santhal Hul of 1855 and 1856 was raised in the Santhal Pargana region against revenue officials, moneylenders and the police, and was led by Sidhu and Kanhu Murmu along with their brothers Chand and Bhairav; its suppression led the colonial government to create a separately administered Santhal Pargana.

The word means the great tumult, and it is the name given to the movement Birsa Munda led in the Chhotanagpur region in 1899 and 1900 against landlords, moneylenders, missionaries and the colonial administration, demanding the restoration of tribal land rights; Birsa died in Ranchi jail in June 1900, and…

Standing in the Giridih district on the Chhotanagpur plateau, Parasnath is the highest point in Jharkhand and is revered by Jains as Sammed Shikhar, the place where a number of their Tirthankaras are believed to have attained liberation, which makes it one of the most important Jain pilgrimage sites in…

Ranchi is the capital of Jharkhand and the seat of its High Court, while Dumka, the headquarters of the Santhal Pargana division in the east of the state, was named the sub-capital so that administration would not be concentrated entirely in one city.

The southern, largely tribal plateau districts of Bihar were separated to form Jharkhand under the Bihar Reorganisation Act, 2000, after a demand that had been pressed since the days of the Chhotanagpur Unnati Samaj and the Adivasi Mahasabha led by Jaipal Singh Munda.

Jharkhand was created on that day under the Bihar Reorganisation Act, 2000, becoming the twenty-eighth state of India, and the date was chosen because it is the birth anniversary of the tribal leader Birsa Munda, now observed nationally as Janjatiya Gaurav Divas.

The Press Council of India first began working in 1966 and functions today under the Press Council Act, 1978; it is a self-regulatory watchdog whose chairman is chosen by a committee of the Chairman of the Rajya Sabha, the Speaker of the Lok Sabha and a member of the Council…

The Kalinga Prize for the Popularisation of Science was created in 1951 with a donation from Biju Patnaik, the founder of the Kalinga Foundation Trust of Odisha, and UNESCO awards it to writers, editors and broadcasters who explain science to ordinary readers; the first prize went to the French physicist…

UNESCO instituted the Guillermo Cano World Press Freedom Prize in 1997 in memory of the Colombian editor of El Espectador, who was murdered outside his office in 1986 for writing against drug cartels; the prize is presented each year on World Press Freedom Day, 3 May.