Q1 · hard · AI-verified
A wire of length L, area of cross-section A has Young's modulus Y. It is stretched by applying a force F. The elastic potential energy stored per unit volume of the wire is:
- F²/(2A²Y)
- F²/(AY)
- F/(2AY)
- F²Y/(2A²)
Q2 · medium · AI-verified
Water rises to a height of 10 cm in a capillary tube. If the same tube is dipped in mercury (which does not wet glass), the mercury level inside the tube compared to outside will:
- Be depressed (go down)
- Rise to the same height of 10 cm
- Rise to 5 cm
- Remain at the same level as outside
Q3 · easy · AI-verified
Which of the following is the SI unit of stress?
- Joule (J)
- Watt (W)
- Newton (N)
- Pascal (Pa)
Q4 · medium · AI-verified
A wire is stretched by 1 mm under a load of 3 kg. By how much will the same wire be stretched by a load of 9 kg? (assume elastic limit is not exceeded)
- 1.5 mm
- 3 mm
- 6 mm
- 9 mm
Q5 · medium · AI-verified
A liquid of density 900 kg/m³ is filled in a container. What is the pressure at a depth of 0.4 m from the surface? (g = 10 m/s²)
- 900 Pa
- 3600 Pa
- 4500 Pa
- 7200 Pa