Explanation

• Venus comes closest to Earth when it is between Earth and the Sun.

• Minimum distance: about 24 million miles (≈ 38 million km).

• This close approach occurs roughly every 584 days.

Additional Information:

• Mercury can be about 33 million miles away when Venus is on the far side of the Sun.

Last verified on 17-01-2026

Explanation

• The magnitude of an earthquake is measured by the Richter scale.
• It measures the energy released by an earthquake.
• The Richter scale was developed in 1935 by Charles F. Richter.
• It is used in seismology (the study of earthquakes).

Last verified on 30-06-2026

Explanation

🔹 1 BTU = 1055.06 Joules (approx.)

🔹 1 BTU = 252 calories (approx.)

🔹 1 Joule = 0.0009478 BTU

🔹 1 kWh = 3412 BTU, linking electrical energy to heat energy.

🔹 Commonly used in heating/cooling systems

🔹 Named after the British engineers who developed early thermal measurements

Last verified on 30-06-2026

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

• RTD (Resistance Temperature Detector) is commonly used to measure temperature in laboratories.
• RTD measures temperature by detecting changes in the electrical resistance of a metal.
• It provides accurate and reliable temperature measurements.
• Platinum is the most commonly used material in RTDs.

Last verified on 26-06-2026

Explanation

• Equal percentage valve characteristic is most suitable for precise flow control at low flow rates.
• In this type of valve, equal increments of valve opening produce equal percentage changes in flow rate.
• It provides better control over a wide range of flow conditions.
• It is commonly used in process industries where accurate regulation is required.

Last verified on 26-06-2026

Explanation

BOD₅ = Initial DO - Final DO  

Given:  

Initial DO = 9 mg/L  

DO after 5 days = 3 mg/L  

BOD₅ = 9 - 3 = 6 mg/L

Last verified on 26-06-2026

Explanation

• Cavitation in a centrifugal pump causes reduced flow and possible damage to pump components.
• Cavitation occurs when vapor bubbles form and collapse inside the pump due to low pressure.
• The collapse of bubbles can cause vibration, noise, and erosion of the impeller.
• It reduces pump efficiency and performance.

Last verified on 26-06-2026