Explanation

• Lahore's smog is mainly caused by pollutants from vehicles reacting with sunlight.
• Nitrogen oxides (NOₓ) and volatile organic compounds (VOCs) form ground-level ozone and fine particles.
• Industrial emissions, crop residue burning, and brick kilns also worsen smog.
• Smog is most severe during the winter season (October–January).

Last verified on 27-07-2026

Explanation

• Geostationary satellites are located directly above the equator. 
• Altitude: About 35,786 kilometers (22,236 miles) above sea level.
• Speed and Direction: Moves from west to east, matching the Earth's rotation speed.
• Time Period: Exactly 24 hours (one rotation day). 

Last updated 26-07-2026 by NA

Explanation

• Wilhelm Conrad Rontgen discovered X-rays
• He was discovered on 8 November 1895.
• He got the Nobel Prize in Physics in 1901.

Additional questions

• The penetrating power of X-rays depends on their frequency

Last updated 26-07-2026 by NA

Explanation

• A Pycnocline is an ocean layer where water density changes rapidly with depth.
• Density changes mainly due to variations in temperature and salinity.
• It acts as a barrier that limits the mixing of surface and deep waters.

Additional information:

• Thermocline: Rapid change in temperature
• Halocline: Rapid change in salinity

Last verified on 26-07-2026

Explanation

• Sunlight travels at the speed of light (~3 × 10⁸ m/s).
• Takes 8 minutes 20 seconds on average to reach Earth.
• Sunlight takes approximately 499 seconds to travel from the Sun to Earth.
• Distance traveled: 150 million km from Sun to Earth.
• Moonlight takes only 1.3 seconds to reach Earth.

Last verified on 13-03-2026