Explanation

• Artist: Leonardo da Vinci (1452–1519)
• Painting Period: 1503–1519
• Origin: Italy
• Current Location: Louvre Museum, Paris, France
• Famous Features: Mysterious smile, sfumato technique, widely copied and recognized globally

Last verified on 18-01-2026

Explanation

• Carbon dioxide (CO₂) is used in fire extinguishers.
• It extinguishes fire by displacing oxygen and cooling the burning material.
• CO₂ fire extinguishers are especially effective for electrical and flammable liquid fires.
• Carbon dioxide is a colorless and non-flammable gas.
• It leaves no residue after use.

Last verified on 09-07-2026

Explanation

• Alexander Graham Bell is credited as the inventor of the telephone.
• He was awarded the first successful patent for it.
• The telephone was invented in 1876.
• Bell made the first-ever telephone call to his assistant Thomas Watson.

Last verified on 31-03-2026

Explanation

• The symbol "√" represents the square root.
• It is called a radical.
• It is used in mathematics to indicate the root of a number.

Last verified on 09-07-2026

Explanation

When pressure is in atm and volume is in liters, use R = 0.0821 L·atm·mol⁻¹·K⁻¹.

The value of R depends on the units, not on the temperature (300 K).

Last verified on 09-07-2026

Explanation

When pressure = kPa and volume = L, use R = 8.314 L·kPa·mol⁻¹·K⁻¹.

This value is used in the Ideal Gas Law: PV = nRT.

Last verified on 09-07-2026

Explanation

Explanation

• Canada Capital is Ottawa.
• Canada Currency is Canadian Dollar.
• Canada official language is English; French.
• Canada located is in Continent North America.
• Canada Primary Religion is Christianity (But Secular Country).
• Canada Parliament called Parliament.

Tricks for Remember

DOLLAR

 Li-Ne-US-Ca-Fi-T-E-A

Mind trick: Li ne(a name) who lives in US likes Coffee(Ca- Fi) and Tea(T-E-A)

**Li-Ne**

Li-Liberia

Ne-New Zealand

**US**

United States

**Ca-Fi**

Ca-Canadian

Fi- Fizzi

**T-E-A**

T-Taiwan

E-Ethiopia

A-Australia

Last verified on 09-07-2026

Explanation

• Power is the rate of doing work or the rate at which energy is transferred.
• It is a scalar quantity (has magnitude only).
• It shows how quickly work is done.
• The SI unit of power is the Watt (W).
• 1 Watt = 1 Joule per second (1 W = 1 J/s).

Additional information:

• Formula: P = W/t = E/t
• SI Base Unit: kg·m²·s⁻³
• Dimension Formula: ML²T⁻³
• James Watt is the scientist after whom the Watt unit is named.

Last verified on 09-07-2026

Explanation