SSC GD Constable GK Questions 2026

A concave lens spreads the light rays slightly before they enter the eye, so the image moves back onto the retina.

Adrenaline is made by the adrenal glands, which sit like caps on top of the two kidneys. It is released in fear, anger or sudden danger, so it is called the "fight or flight" hormone.

The nucleus is called the master or control centre of the cell because it directs all the activities of the cell.

Brass is an alloy of copper and zinc, usually about 70 per cent copper and 30 per cent zinc. Adding zinc makes brass harder than pure copper, gives it a golden-yellow shine and helps it resist corrosion.

Bleaching powder gives off chlorine when it reacts with water, and this chlorine does the bleaching and kills germs. Bleaching powder is calcium oxychloride, CaOCl2, made by passing chlorine gas over dry slaked lime, Ca(OH)2.

Carbon dioxide reacts with lime water to form calcium carbonate, which does not dissolve, and its fine white particles make the water look milky.

Vitamin K is needed to make the clotting proteins, so without it even a small cut keeps bleeding. The liver uses vitamin K to make prothrombin and other clotting factors that turn blood into a clot at a wound.

The medulla oblongata is the breathing centre of the brain, which is why we keep breathing even while asleep. It is the lowest part of the hindbrain and joins the brain to the spinal cord.

Mahatma Gandhi was born on 2 October 1869 at Porbandar in Gujarat, so his 150th birth anniversary fell on 2 October 2019.

Angel Falls, in the Canaima National Park of Venezuela, is the highest uninterrupted waterfall in the world, with a total height of about 979 metres and a single unbroken drop of about 807 metres.

Kolkata earned the name City of Palaces in the colonial era for the grand mansions built by British officials and rich Bengali families along its main streets.

The Ministry of Panchayati Raj is a Union ministry, and like every ministry of the Government of India it works from the national capital, New Delhi.

Shillong is the capital of Meghalaya, the hill state whose name means abode of the clouds. Meghalaya was carved out of Assam and became a full state on 21 January 1972, the same day as Manipur and Tripura.

Part IV, Articles 36 to 51, lists the Directive Principles that guide the State in making laws for a welfare state.

The Fourth Schedule allots the seats of the Rajya Sabha, the Council of States, among the States and Union Territories.

Article 343(1) declares that the official language of the Union shall be Hindi in the Devanagari script, with the international form of Indian numerals for official purposes.

Article 21-A was inserted by the Constitution (86th Amendment) Act, 2002, making free and compulsory education for children aged six to fourteen a Fundamental Right.

Article 154 says the executive power of a State is vested in the Governor, who exercises it directly or through officers under him, exactly as Article 53 does for the President at the Centre.

Magnification is a ratio of two lengths, so the units cancel and it is a pure number. For a mirror or a lens, magnification m equals the height of the image divided by the height of the object (h′/h).

A ray that passes through the optical centre of a thin lens comes out in the same direction, without any bending.