Explanation

The National Aeronautics and Space Administration is an independent agency of the U.S. federal government

NASA is responsible for the civil space program, aeronautics research, and space research.

NASA stands for National Aeronautics and Space Administration

NASA Headquarters: Washington

NASA Founder: Dwight D. Eisenhower

NASA Founded: July 29, 1958

Explanation

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

Explanation

The stratospheric ozone layer is Earth's “sunscreen”  protecting living things from too much ultraviolet radiation from the sun.

Oxygen layer in the atmosphere

Ozone protects us from the harmful ultraviolet radiation of the sun.

Ozone formula: O3

The ozone layer lies approximately 15-40 kilometers (10-25 miles) above the Earth's surface, in the stratosphere.

The ozone layer is depleting: Air pollution

ND17-7-2023

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RY4-12-2022

Explanation

• The percentage of Oxygen in the air is: 21.94%
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• The air in Earth's atmosphere is made up of approximately 78 percent nitrogen and 21 percent oxygen.
  
• Air also has small amounts lots of other gases, too, such as carbon dioxide, neon, and hydrogen.
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• Without oxygen, brain damage is likely after 04-05 mins.
• Joseph Priestly discovered oxygen on August 1, 1774.
• The most abundant element in the Earth's crust is oxygen, making up 46.6% of Earth's mass

Explanation

• Copper is a chemical element with the symbol Cu and atomic number 29. 
• It is a soft, malleable, and ductile metal with a reddish-orange color.

The some major elements with their symbols:

• Hydrogen - H
• Sodium - Na
• Carbon - C
• Nitrogen - N
• Oxygen - O
• Fluorine - F
• Chlorine - Cl
• Potassium - K
• Helium - He
• Neon - Ne
• Calcium - Ca
• Sulphur - S
• Phosphorus - P
• Aluminium - Al
• Magnesium - Mg
• Iron - Fe

Explanation

• The speed of sound in air at 0°C (32°F) is 332 meters per second.

The speed of sound in different materials:

• Air: 332 m/s
• Sea water: 1530 m/s
• Lead: 2160 m/s
• Gold: 3240 m/s
• Brick: 3650 m/s
• Copper: 4760 m/s
• Glass: 5100 m/s
• Aluminium: 6420 m/s

Explanation

• Air is a mixture of different gases.
• Primarily consisting of nitrogen (78%), oxygen (21%), and trace amounts of other gases.

Explanation

• GPS stands for Global Positioning System, a network of satellites orbiting the Earth.
• It provide location information and timing signals to GPS receivers on the ground.

Explanation

Mitochondria is known as powerhouse of cell because it serves as site for synthesis of Adenosine Triphosphate (ATP),

the energy currency of cell, through the process of aerobic cellular respiration.

ATP serves as energy currency for different cell activities.

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A cell consists of three parts:

1.      The cell membrane,

2.      The nucleus, and,

3.      Between the two, the cytoplasm.

Explanation

• An atom is the smallest particle of an element that retains the properties of that element.
• It is the smallest unit of a chemical element, and it cannot be broken down into smaller particles.