Advertisements
Advertisements
प्रश्न
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
पर्याय
energy = `4 "VT" (1/"r" - 1/"R")` is released
energy = `3 "VT" (1/"r" + 1/"R")` is absorbed
energy = `3 "VT" (1/"r" - 1/"R")` is released
energy is neither released nor absorbed
Advertisements
उत्तर
energy = `3 "VT" (1/"r" - 1/"R")` is released
APPEARS IN
संबंधित प्रश्न
Two narrow bores of diameters 3.0 mm and 6.0 mm are joined together to form a U-tube open at both ends. If the U-tube contains water, what is the difference in its levels in the two limbs of the tube? Surface tension of water at the temperature of the experiment is 7.3 × 10–2 N m–1. Take the angle of contact to be zero and density of water to be 1.0 × 103 kg m–3 (g = 9.8 m s–2)
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.
Frictional force between solids operates even when they do not move with respect to each other. Do we have viscous force acting between two layers even if there is no relative motion?
If water in one flask and castor oil in other are violently shaken and kept on a table, which will come to rest earlier?
A capillary tube of radius 1 mm is kept vertical with the lower end in water. (a) Find the height of water raised in the capillary. (b) If the length of the capillary tube is half the answer of part , find the angle θ made by the water surface in the capillary with the wall.
The property of _______ of a liquid surface enables the water droplets to move upward in plants.
The wettability of a surface by a liquid depends primarily on
Obtain an expression for the surface tension of a liquid by the capillary rise method.
For a surface molecule ______.
- the net force on it is zero.
- there is a net downward force.
- the potential energy is less than that of a molecule inside.
- the potential energy is more than that of a molecule inside.
A hot air balloon is a sphere of radius 8 m. The air inside is at a temperature of 60°C. How large a mass can the balloon lift when the outside temperature is 20°C? (Assume air is an ideal gas, R = 8.314 J mole–1K–1, 1 atm. = 1.013 × 105 Pa; the membrane tension is 5 Nm–1.)
