Explanation

Silicon is widely used in semiconductors because:

• It is abundant in nature.
• It has suitable electrical properties.
• It has excellent thermal stability.
• It forms a stable oxide layer (SiO₂) useful in device fabrication.

Note: Germanium was used earlier, and gallium nitride is used for high-power or high-frequency devices, but silicon remains the standard.

Last updated 14-feb-2026

Explanation

• NIC stands for Network Interface Card.
  • It connects a computer to a network or internet.
  • It can be wired (Ethernet) or wireless (Wi-Fi).
  • Every NIC has a unique MAC address.
  • It enables data communication between devices.

Last verified on 07-02-2026

Explanation

• Engrossed means مشغول
• Absorbed means جذب

Last verified on 01-02-2026

Explanation

• Urea fertilizer contains 46% nitrogen (N).
• Urea is a white crystalline solid.
• It is widely used as a fertilizer and animal feed additive.

Last verified on 31-01-2026

Explanation

The main purpose of cellular respiration is to convert chemical energy stored in nutrients (specifically glucose) into ATP (adenosine triphosphate),

They acts as the usable energy currency for cellular processes.

It breaks down glucose in the presence of oxygen to produce ATP, carbon dioxide, and water. 

Explanation

• Oomycetes are fungus-like organisms, often called water molds.
• Although they resemble true fungi, their cell wall composition is different.
• In oomycetes, the cell wall is mainly composed of cellulose.

Additional information:

• True fungi have chitin in their cell walls, while oomycetes have cellulose.
• A common example of oomycetes is Phytophthora, which causes plant diseases.

Last verified on 23-01-2026

Explanation

• Ascorbic Acid is commonly known as Vitamin C.
• It is essential for growth, repair, and maintenance of body tissues.
• Prevents scurvy, a disease caused by Vitamin C deficiency.

Additional information:

Sources of Vitamin C (5):

1. Orange
2. Lemon
3. Guava
4. Strawberry
5. Bell pepper

Functions:

• Antioxidant
• Collagen synthesis
• Strengthens immunity

Last verified on 19-01-2026

Explanation

• The SI unit of energy is the Joule (J).
• It is the unit of energy, work, and heat.

Additional information:

• 1 Joule (J) = 1 Newton × 1 meter
• Calorie – 1 cal = 4.184 J
• Kilowatt-hour (kWh) – 1 kWh = 3.6 × 10⁶ J
• Electronvolt (eV) – 1 eV ≈ 1.602 × 10⁻¹⁹ J
• Erg (CGS unit) – 1 erg = 10⁻⁷ J

Last verified on 17-01-2026

Explanation

• Electron: Discovered by J. J. Thomson, 1897

Additional information:

• Proton: Discovered by Ernest Rutherford, 1919
• Neutron: Discovered by James Chadwick, 1932
• Atomic Model Proposed: Plum Pudding Model
• Significance: First subatomic particle discovered

Last verified on 16-01-2026

Explanation

The troposphere is the lowest layer of the atmosphere

It is where weather occurs and contains about 75% of the atmosphere’s mass.

The principle constituent of the atmosphere of the Earth is called Nitrogen.