Explanation

• Sound travels fastest in diamond, with a speed of approximately 12,000 meters per second (m/s).
• This is because diamond has a very high stiffness and density, which allows sound waves to propagate quickly through the material.

The speeds of sound in different materials:

• Air: 343 m/s
• Water: 1433 m/s
• Wood: 3300-3600 m/s
• Brick: 4176 m/s
• Steel: 6100 m/s
• Diamond: 12000 m/s

Explanation

Invertebrates are animals that do not have a backbone or spinal column. This group includes:

• Insects
• Arachnids (like spiders and scorpions)
• Crustaceans (like crabs and lobsters)
• Mollusks (like squids and octopuses)
• Echinoderms (like starfish and sea urchins)
• Worms

Explanation

Honey has natural antibacterial properties and low moisture, preventing spoilage.

Archaeologists have found edible honey in ancient Egyptian tombs, thousands of years old.

Explanation

PCR (Polymerase Chain Reaction) is the most sensitive and accurate test for detecting viral genetic material.

It can detect even very low amounts of virus in early stages of infection.

Explanation

• Platelets, also called thrombocytes.
• They are blood cells that play a vital role in blood clotting.
• When a blood vessel is injured, platelets aggregate to form a plug that stops the bleeding.

Explanation

Vitamin-B Complex is found in a wide variety of foods including leafy greens, seeds, fruits, and seafood.

It helps in energy production and supports brain and nerve function.

Explanation

HbA (Hemoglobin A) is the normal and most common type of hemoglobin in adults.

HbF (Fetal Hemoglobin) is predominant in fetuses and newborns, later replaced by HbA.

Explanation

A galaxy is a gravitational system of stars, star remnants, interstellar gas, dust, and dark matter.

Earth: diameter of approximately 12,742 kilometers (7,918 miles)

The Sun: diameter of approximately 1,392,684 kilometers (865,374 miles)

Solar System: diameter of approximately 9.2 billion kilometers (5.7 billion miles)

Galaxy (Milky Way): diameter of approximately 100,000 to 200,000 light-years (9.461 × 10^17 to 1.884 × 10^18 kilometers)

Explanation

Galvanized iron sheets have a coating of zinc. 

Galvanization is a process where a layer of zinc is applied to iron or steel to protect it from rusting, making "galvanized iron" essentially iron coated with zinc

Explanation

• The SI unit of energy is the Joule (J).
• It is the unit of energy, work, and heat.