The freezing point of mercury is -39°C. It cannot be used in thermometers for temperatures below this because MCQ with Answer and Explanation

Explanation:
Frequency → pitch perception: higher frequency = higher pitch. Loudness depends on amplitude; timbre on waveform; speed on medium properties. Memory aid: 'Frequency = pitch; Amplitude = loudness'. Basic sound property question frequently tested to verify perceptual attribute associations in competitive exams.

Explanation:
nano = 10⁻⁹. So 1 nm = 10⁻⁹ m. Angstrom = 10⁻¹⁰ m. picometer = 10⁻¹² m.

Explanation:
Water has a specific heat capacity of 4184 J/kg·K, which is very high. This means it heats up and cools down much more slowly than land. During the day, land heats faster than the sea, causing air above it to rise and cool air from the sea to rush in (sea breeze). The reverse happens at night (land breeze).