Work done by a man in carrying a suitcase weighing 10 kg on his head while walking 5 m horizontally (g=10) is MCQ with Answer and Explanation

Explanation:
Time period T = 2π√(L/g) for simple pendulum. Frequency = 1/T. Amplitude is max displacement. Wavelength for waves.

Explanation:
Sound in air is longitudinal.

Explanation:
Pressure cooker seals steam, increasing internal pressure above atmospheric. Higher pressure raises water's boiling point (above 100°C), allowing food to cook at higher temperature, speeding up chemical reactions. Option A is vague; C and D are secondary effects. Memory tip: 'Higher pressure ⇒ higher boiling point ⇒ faster cooking'. This daily-life physics question tests application of pressure-temperature relationship in liquids, frequently appearing in competitive exams. Always recall that phase change temperatures depend on pressure (e.g., water boils below 100°C on mountains).