Advertisements
Advertisements
प्रश्न
A 20 cm long capillary tube is dipped in water. The water rises up to 8 cm. If the entire arrangement is put in a freely falling elevator, the length of water column in the capillary tube will be
पर्याय
8 cm
6 cm
10 cm
20 cm
Advertisements
उत्तर
\[\text{ Height of water column in capillary tube is given by: } \]
\[h = \frac{2Tcos\theta}{r\rho g}\]
\[\text{ A free falling elevator experiences zero gravity }. \]
\[ \Rightarrow h = \frac{2Tcos\theta}{r\rho0} = \infty \]
\[\text{ But, h = 20 cm (given)}\]
\[\text{ Therefore, the height of the water column will remain at a maximum of 20 cm} .\]
APPEARS IN
संबंधित प्रश्न
Explain why Water on a clean glass surface tends to spread out while mercury on the same surface tends to form drops. (Put differently, water wets glass while mercury does not.)
Explain why A drop of liquid under no external forces is always spherical in shape
The total energy of free surface of a liquid drop is 2π times the surface tension of the liquid. What is the diameter of the drop? (Assume all terms in SI unit).
When a glass capillary tube is dipped at one end in water, water rises in the tube. The gravitational potential energy is thus increased. Is it a violation of conservation of energy?
A heavy mass is attached to a thin wire and is whirled in a vertical circle. The wire is most likely to break
Water rises in a vertical capillary tube up to a length of 10 cm. If the tube is inclined at 45°, the length of water risen in the tube will be
A cubical box is to be constructed with iron sheets 1 mm in thickness. What can be the minimum value of the external edge so that the cube does not sink in water? Density of iron = 8000 kg/m3 and density of water = 1000 kg/m3.
How much amount of work is done in forming a soap bubble of radius r?
Define surface tension.
Numerical Problem.
A stone weighs 500 N. Calculate the pressure exerted by it if it makes contact with a surface of area 25 cm2.
A certain number of spherical drops of a liquid of radius R coalesce to form a single drop of radius R and volume V. If T is the surface tension of the liquid, then
What do you mean by capillarity or capillary action?
Obtain an expression for the excess of pressure inside a
- liquid drop
- liquid bubble
- air bubble
The excess of pressure, due to surface tension, on a spherical liquid drop of radius 'R' is proportional to ______.
The upward force of 105 dyne due to surface tension is balanced by the force due to the weight of the water column and 'h' is the height of water in the capillary. The inner circumference of the capillary is ______.
(surface tension of water = 7 × 10-2 N/m)
Soap solution is used for cleaning dirty clothes because ______.
Why is raindrop spherical in nature?
Two mercury droplets of radii 0.1 cm. and 0.2 cm. collapse into one single drop. What amount of energy is released? The surface tension of mercury T = 435.5 × 10–3 Nm–1.
The sufrace tension and vapour pressure of water at 20°C is 7.28 × 10–2 Nm–1 and 2.33 × 103 Pa, respectively. What is the radius of the smallest spherical water droplet which can form without evaporating at 20°C?
A liquid flows out drop by drop from a vessel through a vertical tube with an internal diameter of 2 mm, then the total number of drops that flows out during 10 grams of the liquid flow out ______. [Assume that the diameter of the neck of a drop at the moment it breaks away is equal to the internal diameter of tube and surface tension is 0.02 N/m].
