Explanation

• Surface tension decreases as temperature increases.
• Higher temperature increases the kinetic energy of liquid molecules, weakening the effect of intermolecular cohesive forces at the surface.
• Surface tension becomes nearly zero at the critical temperature, where the distinction between liquid and gas disappears.
• Water has a surface tension of approximately 72.8 mN/m at 20°C.

Last verified on 16-10-2026

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

• Gamma rays have the highest frequency, shortest wavelength, and highest photon energy.
• They have strong penetrating ability and can pass through many materials.

Additional information:

Electromagnetic Spectrum (High to Low Frequency):

1. Gamma rays
2. X-rays
3. Ultraviolet rays
4. Visible light
5. Infrared rays
6. Microwaves
7. Radio waves

Last verified on 15-10-2026

Explanation

• The amplitude of a sound wave determines its loudness.
• Greater amplitude generally produces a louder sound.
• While smaller amplitude produces a quieter sound.

Additional information:

• Frequency: Determines pitch (high or low sound).
• Wavelength: The distance between two consecutive points in the same phase, such as two crests.

Last verified on 15-10-2026

Explanation

• A velocity–time graph shows how velocity changes with time.
• The slope gives acceleration.
• The area under the graph represents motion covered.
• It connects velocity with displacement.

Last verified on 22-05-2026