Explanation

• The power of a lens (P) is given by the formula:
• P = 100/f (cm) or P = 1/f (m)
• Focal length (f) and power (P) are inversely proportional.
• So, if the focal length increases, the power decreases.

Additional information:

• Convex lens: Converging lens
• Unit of power: Diopter (D)

Last verified on 10-02-2026

Explanation

• The capsule in bacteria is an outer protective layer.
• It prevents the bacteria from being destroyed by the host immune system, increasing pathogenicity (ability to cause disease).
• Made of polysaccharides in most bacteria.

Last verified on 10-02-2026

Explanation

• Organic compounds (like hydrocarbons, sugars, fats) are highly combustible.
• This is due to their high carbon content, which releases energy when burned.
• Carbon forms stable bonds that release heat and energy during combustion.

Last verified on 10-02-2026

Explanation

• Vitamin K is essential for blood clotting.
• A deficiency can cause delayed clotting and excessive bleeding after injury.
• It is a fat-soluble vitamin found in green leafy vegetables and produced by gut bacteria.

Additional information:

• Vitamin A: Vision, skin, immune function
• Vitamin D: Calcium absorption, bone health

Last verified on 10-02-2026

Explanation

• Pressure is a fundamental physical quantity that is defined as the force exerted per unit area.
• It is a measure of the strength of a force acting on a surface.
• It is typically measured in units such as Pascals (Pa) or pounds per square inch (PSI).

Last verified on 10-02-2026

Explanation

• Xylem is the plant tissue responsible for transporting water and minerals from roots → stem → leaves.
• It consists of continuous tubes made of dead cells for easy water flow.

Additional information:

• Phloem: Transports food (sugars) from leaves to other parts

Explanation

• 10 Downing Street, colloquially known as Number 10.
• It is the official residence and office of the British Prime Minister.
• It located on Downing Street in London's City of Westminster.

Additional information:

• It was constructed between 1682 and 1684 by architect Kenton Couse.
• The building, over 300 years old, boasts approximately 100 rooms.
• It was officially designated on 14 January 1970.

Last verified on 02-02-2026

Explanation

• Red Sea Location: Between Arabian Peninsula (Asia) and Northeastern Africa
  • Type: Sea (arm of the Indian Ocean)
  • Connection to Ocean: Via Bab-el-Mandeb Strait
  • Distinct Feature: Unlike the Caspian or Aral Seas, it has direct connection to the ocean
  • Length: ~2,300 km long
  • Borders: Egypt, Sudan, Eritrea (Africa) and Saudi Arabia, Yemen (Asia)

Last verified on 10-02-2026

Explanation

• South Sudan is the most recently independent African country.
• It gained independence on 9 July 2011 from Sudan after decades of civil war.
• Capital: Juba
• Population: ~11 million (2025 estimate)
• Official language: English

Additional information:

• Currency: South Sudanese Pound (SSP)
• Largest ethnic group: Dinka
• Flag colors: Black, Red, Green, Blue, Yellow
• South Sudan became the 193rd member of the United Nations in 2011.

Last verified on 10-02-2026

Explanation

• Algeria is the largest country in Africa by land area and population.

Additional information:

• The second largest by area: Congo
• The second largest by population: Ethiopia

Last verified on 10-02-2026