Explanation

• A Telescope is an optical instrument used to observe distant objects such as stars, planets, and galaxies.
• It collects and magnifies light or other forms of electromagnetic radiation.
• The term “telescope” was coined in 1611 by the Greek mathematician Giovanni Demisiani.

Last verified on 10-03-2026

Explanation

• The atmospheric pressure at any place is measured by a Barometer.
• The barometer was invented by Evangelista in 1644.

Last verified on 10-03-2026

Explanation

• Antoine Lavoisier, a French chemist, is credited with discovering the law of conservation of mass in 1789 (1785).
• He demonstrated that matter cannot be created or destroyed in a chemical reaction, only transformed from one substance to another.

Last verified on 10-03-2026

Explanation

• Photosynthesis is the process by which green plants, algae, and some bacteria convert sunlight, water, and carbon dioxide into food (glucose).
• It occurs in the chloroplasts of plant cells using chlorophyll.
• The byproduct of this process is oxygen, which is released into the atmosphere.

Last verified on 10-03-2026

Explanation

• First man who travelled in Space was Yuri Gagarin in 1961.
• Yuri Gagarin was a Soviet pilot and cosmonaut.
• He aboard the first successful crewed spaceflight, became the first human to journey into outer space.

Additional information:

• First man who Walk in Space was Alexei Leonov in 1965.
• First man who Walk on Moon was Neil Armstrong in 1969.

Last verified on 10-03-2026

Explanation

• The nervous system is the body system that controls and coordinates the functions of all other organ systems.
• It allowing for integration and regulation of various bodily functions.
• It consists of the brain, spinal cord, nerves, and sensory organs.

Last verified on 09-03-2026

Explanation

• The ozone layer acts as Earth’s natural sunscreen, protecting life from the sun’s harmful ultraviolet (UV) radiation.
• UV radiation can cause skin cancer, eye damage, and harm to plants and animals.

Additional information:

• Chemical Formula: O₃ (three oxygen atoms)
• Layer Location: Stratosphere, 15–40 km above Earth
• Function: Absorbs UV-B and UV-C rays from the Sun
• Depletion Causes: Air pollution, CFCs, industrial chemicals
• Protection Measures: Reduce CFC use, ozone-friendly products

Last verified on 09-03-2026

Explanation

• Pressure can be defined as the force acting per unit area.
•  Pascal (Pa) is the SI unit of pressure.
• In SI base units kg⋅m−1⋅s−2
• Derivations from other quantities: p = F / A
• Dimension unit: M L^−1 T^-2

Additional information 

The SI unit of energy/work is the joule (J)

Last updated on 09-03-2026

Explanation

Explanation