Due to the surface tension free liquid drops & bubbles are spherical, if effect of gravity & air resistance are negligible. As ∆r is very small, ∆r2 is neglected. Equation (5) is called as Laplace’s Law of spherical membrane for drops. For, soap bubble, there are two sides.
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Why are drops and bubbles spherical Class 11?
A sphere has the minimum surface area of all shapes that enclose a given volume. So the surface tension tends to minimize the surface area and to compensate it the molecules group together to form the best possible shape for the situation, which is a sphere. Thus the bubbles are spherical in shape.
What is drop and bubbles?
A drop is a little round or pear-shaped portion of liquid hanging, falling, or sticking to a surface. A bubble is a thin liquid spherical that encloses air. A bubble is filled with air, whereas a drop is filled with liquid.
Why are drops and bubbles spherical chapter name?
Because of surface tension, the wall tension required for the formation of drops or bubbles is provided. The tendency to minimise surface area, causes the wall tension to be pulled inwards, directed at all sides, thereby leading to a spherical shape.
Where are drops and bubbles spherical?
The surface of liquid behaves like a stretched membrane and has a tendency to acquire minimum surface area. The sphere has minimum surface area when compared to other shapes of same volume
Therefore, drops and bubbles acquire spherical shape in order to have the minimum surface area.
Why are bubbles always spherical?
Why are bubbles round? Scientists refer to bubbles as “minimal surface structures.” This means that they always hold the gas or liquid inside of them with the least possible surface area. The geometric form with the least surface area for any given volume is always a sphere, a round shape.
Why drop is spherical in shape?
The cohesive forces between liquid molecules is responsible for the surface tension. The molecules of water on the surface don’t have like molecules around it.So the water droplets tend to be pulled into shape of spherical due to cohesive forces. Thats why, the drop of water is always spherical.
Why bubbles and droplets are round?
The attraction of the molecules, called surface tension, contracts the soap bubble to the smallest possible area. At the same time, the air inside the soap bubble presses against it. The bubble forms into a sphere because it can contain the largest contents with the smallest circumference.
Why are drops and bubbles are spectacle?
Solution : Small drops and bubbles of liquid are spherical because of surface tension.
What is liquid drop in physics?
The liquid-drop model is a model describing the atomic nuclei in nuclear physics. The molecules in a drop of liquid behave like nucleons, that is, neutrons and protons. The model is designed on the basis of certain assumptions. There are four major assumptions made while designing the liquid-drop model.
Why a soap bubble has two surface area?
Picture a soap bubble. The surface tension balances the outward force due to the pressure difference between the inside and the outside air. We have two surfaces, the inner and the outer surface of the bubble.
What is meant by capillarity Class 11?
Hint: Capillarity is a phenomenon by which the liquid moves without the help of gravity. The liquid level rises to some height against the gravitational force, through the narrow tube. This action is due to the phenomenon of surface tension of the liquid.
Why do bubbles minimize surface area?
In the volume of a liquid The driving force behind this shape is the surface tension of the bubble interface. This is attempting to minimize the surface area of the bubble. For an enclosed surface with no boundary conditions, only a fixed volume, the shape with the minimum surface area is a sphere.
What is capillary rise drop?
Capillary is a phenomenon of rising or falling of liquid surface in a small tube compared to the adjacent normal liquid level. The rise of liquid in tube known as capillary rise while depression of fluid level is known as capillary fall.
What is angle of contact Class 11?
UPLOAD PHOTO AND GET THE ANSWER NOW! Solution : The angle between the tangent drawn on a force surface and the surface under the liquid in contact with it, is known as angle of contact. Answer.
Why is the shape of the droplets differ?
So, some droplets are spherical while the others are not. A droplet having a non-spherical shape contrasts what we learned in high-school physics: droplets assume a spherical shape because of the force of surface tension as it tries to minimize the surface area of the droplet for a given volume.
Why do liquids form droplets?
Liquid forms drops because it exhibits surface tension. A simple way to form a drop is to allow liquid to flow slowly from the lower end of a vertical tube of small diameter. The surface tension of the liquid causes the liquid to hang from the tube, forming a pendant.
What keeps soap bubbles stable class 11?
In a soap bubble because of the pressure difference between the inside and the outside layer, the surface friction balances the external force.
What is the volume of the bubble?
The air pressure is the same as the pressure of the surrounding water, and the volume of the bubble can be determined by the volume formula of a sphere V=43πr3.
What is the shape of air bubble?
That shape happens to be a sphere.
What are bubbles made of?
The wall of a bubble is actually made of three layers; An inner and outer layer made of soap or detergent and a layer of water in between. It’s like a water sandwich with soap as the bread. Water evaporating from the bubble film makes the bubble film so thin that the bubble pops. The wall of a bubble is extremely thin.
Why do rain fall in drops?
Rain always fall in drops and not as a continuous stream. This is mainly due to the surface tension of water caused due to the tendency of water molecules to stick together. Therefore, larger drops split into smaller ones.
What is SI unit of surface tension?
The SI unit of Surface Tension is Newton per Meter or N/m.
What is the shape of water droplets?
KnowHOW team explains: Water drops, or, for that matter, the drops of any other liquid, are spherical in shape due to a phenomenon called surface tension.
Is a bubble a perfect sphere?
Bubbles are round because there is equal pressure all around the outside of the bubble. The perfectly round shape that most bubbles have is called a sphere.