Explanation

• Kilometers per second: ≈ 300,000 km/s
• Speed in vacuum: 299,792,458 m/s
• Approximate value: 3 × 10⁸ m/s
• Symbol: c
• Distance traveled in 1 second: About 300,000 km
• Light from the Sun takes about 8 minutes 20 seconds to reach the Earth.

Last verified on 16-05-2026

Explanation

• The lungs are located in the thoracic cavity.
• The thoracic cavity is the chest cavity protected by the rib cage.
• It contains the lungs, heart, trachea, and major blood vessels.
• The lungs are enclosed by the pleural membranes.
• This cavity plays a vital role in breathing and respiration.

Last verified on 18-07-2026

Explanation

• White goods are durable consumer goods, mainly large household electrical appliances.
• The term originally referred to appliances that were usually finished in white enamel.
• These products are designed for long-term household use.
• Examples: Refrigerator, Washing Machine, Air Conditioner, Dishwasher, Deep Freezer

Additional information:

• Brown goods include entertainment electronics such as TVs, radios, and audio systems.

Last verified on 18-07-2026

Explanation

• The speed of sound is maximum in solids 
• Because particles are tightly packed, allowing faster vibration transfer.
• In iron, sound travels around 5120 m/s,
• Much faster than in air (343 m/s) or water (1482 m/s).

Last updated 17 july 2026 by NA

Explanation

• Surface tension prevents water from penetrating waterproof materials.

Additional information 

• Friction: Force that opposes the motion between two surfaces in contact.
• Adhesion: Attraction between molecules of different substances.
• Gravity: Force that pulls objects toward the Earth

Last updated by NA on 16-07-2026

Explanation

• Insulin and glucagon regulate blood glucose (sugar) levels.
• Insulin lowers blood sugar by helping cells absorb glucose.
• Glucagon raises blood sugar by releasing stored glucose from the liver.
• Both hormones are produced by the pancreas.
• They work together to maintain normal blood sugar levels.

Verified & Updated

Explanation

• Protease is the enzyme that breaks down proteins into amino acids.
• It helps digest proteins in the digestive system.
• Proteases are produced in the stomach, pancreas, and small intestine.
• Amino acids are absorbed by the small intestine.

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Explanation

Given ratio = Nitrogen : Sulphur : Phosphorus = 5 : 3 : 2  

Total parts = 5 + 3 + 2 = 10  

Total weight = 200 kg  

Value of 1 part = Total weight / Total parts  

= 200 / 10 = 20 kg  

Initial weight of Nitrogen = 5 x 20 = 100 kg  

Initial weight of Sulphur = 3 x 20 = 60 kg  

Initial weight of Phosphorus = 2 x 20 = 40 kg  

100 kg of Nitrogen is added.  

New weight of Nitrogen = 100 + 100 = 200 kg  

Verified & Updated

Explanation

• An endemic disease is a disease that is constantly present in a specific population or geographic area.
• Examples:
• Malaria
• Chickenpox
• Dengue Fever

Additional information 

• Epidemic: A sudden, unexpected spike in cases within a specific community or region.
• Pandemic: An epidemic that has spread globally, covering multiple countries or continents.

Last updated by NA on 16-07-2026

Explanation

• Meteorology is the science of the atmosphere and weather patterns.

Additional information 

• Climatology: weather patterns and climate changes over time.
• Oceanography:  oceans, marine ecosystems, currents, and the seabed.
• Geology: Earth's solid rocks, minerals, and the physical history of its structure.
• Astronomy: celestial objects, space, and the physical universe beyond Earth

Last updated by NA on 16-07-2026