Advertisements
Advertisements
प्रश्न
A 5.0 cm long straight piece of thread is kept on the surface of water. Find the force with which the surface on one side of the thread pulls it. Surface tension of water = 0.076 N m−1.
Advertisements
उत्तर
Given:
Length of thread l = 5 cm = 5 × 10−2 m
Surface tension of water T = 0.76 N/m
We know that:
F = T × l = 0.76 × 5 × 10−2
= 3.8 × 10−3 N
Therefore, the water surface on one side of the thread pulls it with a force of 3.8 × 10−3N
APPEARS IN
संबंधित प्रश्न
A raindrop of diameter 4 mm is about to fall on the ground. Calculate the pressure inside the raindrop. [Surface tension of water T = 0.072 N/m, atmospheric pressure = 1.013 x 105 N/m2 ]
Draw a neat labelled diagram showing forces acting on the meniscus of water in a capillary tube.
Fill in the blanks using the word(s) from the list appended with each statement
Surface tension of liquids generally . . . with temperatures (increases / decreases)
State any two characteristics of the angle of contact
The contact angle between water and glass is 0°. When water is poured in a glass to the maximum of its capacity, the water surface is convex upward. The angle of contact in such a situation is more than 90°. Explain.
A heavy mass is attached to a thin wire and is whirled in a vertical circle. The wire is most likely to break
The rise of a liquid in a capillary tube depends on
(a) the material
(b) the length
(c) the outer radius
(d) the inner radius of the tube
The lower end of a capillary tube is immersed in mercury. The level of mercury in the tube is found to be 2 cm below the outer level. If the same tube is immersed in water, up to what height will the water rise in the capillary?
A metal piece of mass 160 g lies in equilibrium inside a glass of water. The piece touches the bottom of the glass at a small number of points. If the density of the metal is 8000 kg/m3, find the normal force exerted by the bottom of the glass on the metal piece.
A solid sphere of radius 5 cm floats in water. If a maximum load of 0.1 kg can be put on it without wetting the load, find the specific gravity of the material of the sphere.
Derive an expression for capillary rise for a liquid having a concave meniscus.
How does the friction arise between the surfaces of two bodies in relative motion?
Define the surface tension of a liquid.
Obtain an expression for the surface tension of a liquid by the capillary rise method.
If the surface tension of a soap solution is 3 × 10-2 N/m then the work done in forming a soap film of 20 cm × 5 cm will be ______.
Soap solution is used for cleaning dirty clothes because ______.
A drop of water and a soap bubble have the same radii. Surface tension of soap solution is half of that of water. The ratio of excess pressure inside the drop and bubble is ______.
The surface tension of soap solution is 25 × 10-3 Nm-1. The excess of pressure inside a soap bubble of diameter 1 cm is ______.
