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

• Speed: ~300,000 km/s (exactly 299,792 km/s)
• Symbol: c
• Medium: Vacuum (space)
• Type: Electromagnetic waves
• Constant: Universal physical constant

Last verified on 16-05-2026

Explanation

• Nitrogen (N₂) → 78%

Additional information:

• Oxygen (O₂) → 21%
• Argon (Ar) → 0.93%
• Carbon dioxide (CO₂) → 0.04% (approximately)
• Other gases → Trace amounts

Last verified on 28-06-2026

Explanation

• Farad (F) is the SI unit of capacitance of a capacitor.
• Capacitance is the ability of a capacitor to store electric charge.
• One farad is equal to one coulomb of charge stored per one volt of potential difference.
• The unit is named after scientist Michael Faraday.

Additional information:

• Energy / Work → Joule (J)
• Electric Charge → Coulomb (C)
• Pressure → Pascal (Pa)
• Electric Current → Ampere (A)
• Power → Watt (W)
• Resistance → Ohm (Ω)
• Temperature → Kelvin (K)
• Torque → Newton metre (N·m)
• Velocity → metre per second (m/s)
• Acceleration → metre per second² (m/s²)

Last verified on 28-06-2026

Explanation

• CFCs, carbon dioxide (CO₂), and methane (CH₄) are all greenhouse gases.
• Carbon dioxide traps heat in the atmosphere and increases temperature.
• Methane is a very strong greenhouse gas with high warming effect.
• CFCs also damage the ozone layer and act as greenhouse gases.

Last verified on 16-06-2026