Explanation

White clothes reflect most of the sunlight, which helps keep the body cooler compared to darker clothes, which absorb more heat.

Explanation

Gamma radiation is the most dangerous type of radiation.

it has high energy and can penetrate most materials, including human tissue.

It is highly penetrating and can cause significant biological damage.

Explanation

Geographers broadly divide the Earth into three separate climate zones: 

1. Tropical (near the Equator)
2. Temperate (north and south of the Equator)
3. Polar (the farthest Northern and Southern regions)

Explanation

• The speed of sound in air at sea level and 20°C (68°F) is approximately 343 meters per second.
  

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

Guglielmo Marconi was an Italian inventor and electrical engineer who is credited with the invention of the radio.

His work on long-distance radio transmission and the development of Marconi's law revolutionized wireless communication in the early 20th century.

Explanation

Railway tracks are made of steel, which expands in summer heat.

The gaps between rails allow space for this expansion, preventing the tracks from buckling or derailing trains.

Explanation

• Comets: huge masses of snow and rocks that revolve around the Sun in orbits.
• Comets: have huge glowing tails.
• Halley's Comet was last seen in: 1986
• Halley's Comet will be next seen in: 2062

Explanation

A voltmeter is used to measure the potential difference (voltage) across two points in a circuit.

It is connected in parallel with the component whose voltage is being measured.

Explanation

Earth's circumference (the distance all the way around the equator) is 24,901 miles (40,075 kilometers).

Its diameter (the distance from one side to the other through Earth's center) is 7,926 miles (about 12,756 kilometers).

Density: 5.51 g/cm3

Age: 4.453 billion years

Explanation

The distance traveled by a body in unit time is called the speed of the body.

S.I. unit of speed is meter per second (ms−1).

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