RRB Group D GK Questions 2026

Two steps are needed. First, the focal length must be converted to metres: 50 centimetres is 0.5 metre.

The power of a lens measures how strongly it converges or diverges light, and it is defined as one divided by the focal length expressed in metres.

The least distance of distinct vision, also called the near point, is the smallest distance at which an object can be held and still be seen clearly without strain.

The iris is the coloured ring of muscle lying just behind the cornea. By contracting and relaxing it makes the central opening, the pupil, smaller in bright light and larger in dim light, and in this way it regulates how much light falls on the retina.

A soap film is extremely thin, and light reflected from its front surface meets light reflected from its back surface.

The cornea is the thin, transparent, slightly bulging membrane that forms the front surface of the eyeball, and light must pass through it before reaching anything else.

Myopia, or short-sightedness, is the defect in which nearby objects are seen clearly but distant objects look blurred. It arises either because the eye lens has become too converging, that is its focal length is too short, or because the eyeball has grown too long from front to back.

A nineteenth century scholar and reformer, he compiled Hemkosh, which was the first Assamese dictionary to be arranged on etymological lines and which fixed much of the modern spelling of the language; the work was published after his death.

Manvini Bhavai is his novel of rural Gujarat during a devastating famine, written from the inside of peasant life, and it is the work for which he received the Jnanpith Award.

A leading writer of the Jonaki era that began with the magazine of that name in 1889, he wrote humour, satire, plays and the much loved collection of folk tales Burhi Aair Sadhu, meaning Grandmother Tales, and he composed O Mur Apunar Desh, which is now the state song of…

The fifteenth and sixteenth century Vaishnava saint founded the Ekasarana faith and shaped much of Assamese cultural life: he composed the devotional songs known as Borgeet, wrote the one-act plays called Ankiya Nat that are staged as Bhaona, gave rise to the dance tradition now called Sattriya, and wrote the…

Writing in the fourteenth century, he put the Ramayana into Assamese verse in seven books, which is what the name Saptakanda records, and the work is counted among the first translations of the epic into any modern Indian language.

He is called the father of Odia fiction and of modern Odia prose and is titled Utkala Byasa Kabi, and his novel Chha Mana Atha Guntha is a sharp, ironic account of how a scheming landlord dispossesses a poor weaver couple of their small plot of land.

The fifteenth century poet composed the Odia Mahabharata, along with the Chandi Purana and the Vilanka Ramayana, and in writing the epic in the speech of ordinary people rather than in Sanskrit he earned the title Adikavi, the first poet of Odia.

Her poem Ajj Aakhaan Waris Shah Nu calls on the old poet of Heer to speak again over the suffering of Partition, her novel Pinjar tells the story of an abducted woman of those years, and she received the Jnanpith Award in 1981 for the collection Kagaz Te Canvas.

His Heer, composed in 1766, is the version of the tragic love story of Heer and Ranjha that is still sung and quoted across Punjab, and it is the answer whenever an examiner names the qissa.

He published Saraswatichandra in four parts between 1887 and 1901, and the long social novel about a learned young man and the world around him is treated as the work with which the modern Gujarati novel begins.

Narsinh Mehta was a fifteenth century devotional poet of Gujarat who is honoured as the Adi Kavi, the first poet of the language, and his bhajan Vaishnav Jan To lists the qualities of a true devotee, which is why Gandhi made it part of the daily prayer at his ashram.

He is credited with the Samaranganasutradhara on architecture and mechanics and the Saraswatikanthabharana on poetics, and with the Bhojashala at Dhar and the great lake and Shiva temple at Bhojpur.

The Chandelas ruled Jejakabhukti, the Bundelkhand region, from Khajuraho and Mahoba, and built the Khajuraho group of temples in the Nagara style between about 950 and 1050; the Lakshmana temple belongs to Yasovarman, the Vishvanatha temple to Dhanga and the great Kandariya Mahadeva temple to Vidyadhara.