Explanation

• Theory proposed by: Charles Darwin
• Book published: 1859
• Book name: On the Origin of Species
• Key concept: Natural Selection
• Voyage that inspired him: HMS Beagle expedition (1831–1836)

Last verified on 21-06-2026

Explanation

• Picosecond (ps) = 10⁻¹² seconds
• SI prefix “pico” means 10⁻¹².
• 1 picosecond = one trillionth of a second.

Additional information:

• Microsecond (μs) = 10⁻⁶ seconds
• Nanosecond (ns) = 10⁻⁹ seconds
• Millisecond (ms) = 10⁻³ seconds
• Femtosecond (fs) = 10⁻¹⁵ seconds
• Attosecond (as) = 10⁻¹⁸ seconds
• Zeptosecond (zs) = 10⁻²¹ seconds
• Yoctosecond (ys) = 10⁻²⁴ seconds

Last verified on 17-06-2026

Explanation

• Ornithology is the branch of zoology that deals with the study of birds.
• It includes bird behavior, classification, and migration patterns.
• Scientists who study birds are called ornithologists.

Last verified on 10-06-2026

Explanation

• Herpetology is the branch of zoology that studies reptiles and amphibians.
• Reptiles include: snakes, lizards, crocodiles, turtles.
• Amphibians include: frogs, toads, salamanders.
• The word comes from Greek “herpeton” meaning creeping animal.

Last verified on 09-06-2026

Explanation

When white light passes through a prism, it splits into 7 colors, forming a spectrum known as a rainbow:

1. Red
2. Orange
3. Yellow
4. Green
5. Blue
6. Indigo
7. Violet

The separation of visible light into its different colours is known as dispersion.

Last verified on 08-06-2026

Explanation

• The SI unit of electric current is Ampere (A).
• Electric current measures the flow of electric charge.
• Defined using the elementary charge (e = 1.602176634 × 10⁻¹⁹ C).
• Named after: André-Marie Ampère (scientist).
• 1 Ampere = 1 Coulomb per second (1 A = 1 C/s).

Last verified on 08-06-2026

Explanation

• The usual gases used for lifting airships are hydrogen and helium.
• Hydrogen is the lightest known gas and thus has great lifting capacity,
• Helium is not as buoyant but is far safer than hydrogen because it does not burn.

Last verified on 01-04-2026

Explanation

• The largest planet in our solar system is Jupiter.
• 5th planet
• 79 known moons (Maximum number of moons)
• The Great Red Spot is a prominent feature
• Giant planet and the fastest-rotating planet 
• Rotates approximately once every 10 hours.
• Age is about 4.603 billion years.

Additional information

• Mercury is the smallest planet of the solar system.

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Last updated by NA on 25-April-2026

Explanation

• The average normal body temperature is generally accepted as 98.6°F (37°C).
• A temperature over 100.4°F (38°C) means you have a fever.

Additional Information:

• Hypothermia is the term used for temperature less than 36.50°C.
• Mild Pyrexia is the term used for temperature (99-100°F).
• Moderate Pyrexia is the term used for temperature (100-103°F).
• Severe Pyrexia is the term used for temperature (103-105°F).

Explanation

• Vitamin D is essential for healthy bones.
• Its deficiency leads to Rickets in children and Osteomalacia in adults.
• Sunlight is the best natural source of Vitamin D.

Additional information:

Deficiency effects:

• Bone pain
• Weak bones
• Skeletal deformities

Other Vitamin Deficiencies:

• Vitamin A: Night blindness
• Vitamin C: Scurvy
• Vitamin B7 (Biotin): Hair fall

Last verified on 17-01-2026