The spherical shape of rain droplets is due to

More • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • The correct option is B Surface tension The spherical shape of rain droplets is due to lowest surface tension of sphere. The lowest energy state of any liquid will be when its surface area is minimum. Hence it tries to decrease the surface area of the liquid to a minimum value. When a drop is formed, upward thrust due to surface tension balances the gravitational force. 2 π r γ = m g, where r and m are radius and mass of spherical droplet respectively and g is accelearation due to gravity.

Hint: Sphere has the least surface area for a given volume.Shape of the liquid contained things is determined by the various factors. Complete answer: When the surface area of the liquid is increased, molecules from the interior rise to the surface. In this process, work is done by the molecules against the intermolecular forces and the energy is stored as potential energy. In a stable equilibrium the system tries to minimize this potential energy and hence tries to minimize the surface area. This property is exhibited as surface tension. The surface tension of a liquid is defined as the force per unit length in the plane of the liquid, acting at right angles on either side of an imaginary line drawn in that surface. It has an S.I. unit if N/m. As a result of it, a raindrop in absence of any external force tries to minimize its surface area. For a given volume of liquid, the sphere has the minimum surface area. Thus, a rain-drop is spherical in shape. Note: As mentioned in the absence of any external force, the rain drop is spherical. However, while falling on earth, it is also acted upon by gravity. Gravity distorts the shape, and stretches the sphere to a droplet shape. Density of the liquid has nothing to do with the shape of it. Also considering the droplet to be small, the atmospheric pressure acts equally on all sides, thus preserving the spherical shape.

This paper concerns the measurement and prediction of rainfall noise with a particular focus on measurements made using the method described in the ISO rainfall noise standard. Rainfall noise is generated by rain impacting on a surface which excites the surface producing noise. Here, several different models for the force produced by a water droplet impacting on a flat inclined surface are presented. These models are designed for the nominal intense and heavy raindrops described in the ISO standard and are validated against experimental measurements. The best-performed models have been incorporated into theoretical methods for predicting the noise produced by rainfall on a flat inclined panel. These methods are used to produce noise level predictions for Introduction The forces produced when raindrops impact on a roof can be a significant source of noise, particularly for lightweight rooves [1]. The forces produced by the raindrop impacts induce vibration in the roof structure producing sound, which can be very disruptive to the occupants below if there is insufficient insulation. For this reason, standards for some buildings (e.g. school buildings in New Zealand and the UK [2], [3]) attempt to ensure that roof systems are constructed to produce rain noise of an acceptably low level. The rain noise produced by a roof system (or a component of a roof system – e.g. a skylight) can be assessed experimentally using the methods described in ISO 10140-5:2010/Amd.1:2014 [4] and A...

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A man stands by a stream holding a box. Animated flowers and plants sprout from the top. Wiggly arrows point up from the water and from the plants towards the sky. NARRATOR: Now, this is a familiar scene. The sun's heat causes water from plants, lakes and oceans to turn from a liquid to a vapour. Text on screen - 'Evapotranspiration.' NARRATOR: High in the atmosphere, the water vapour then cools down and condenses from a gas back into a liquid. Text on screen - 'Condensation.' Shot of clouds. Thunder rumbles and rain patters. A man in a business suit stands in the rain at a bus stop. Another man stands in a snow-covered field. Text on screen - 'Precipitation.' NARRATOR: The liquid water then falls back to the surface in the form of rain, snow, ice or hail. Water runs off into streams, lakes and oceans, or is stored in the ground or in snowpack. Text on screen - 'Runoff.' This is the water cycle, and it describes how our most vital resource moves through the whole Earth system. Text on screen - 'The Water Cycle.' Arrows forming a circle link pictures of evapotranspiration, condensation, precipitation and runoff together. NARRATOR: But like most things in our world, when we look at the tiny parts that make up the whole, we can learn a lot more about the phenomena. Animation of a circular ball of water in the air. NARRATOR: Take the shape of a single raindrop. Small droplets of water in the atmosphere are spherical in shape due to the surface tension, or skin, of the water mo...

Why the droplet of rain is spherical? When it rains, the droplets of water often form a spherical shape. This is due to the intermolecular forces of attraction and the surface tension of water molecules. The intermolecular forces of attraction attempt to keep the water molecules from touching the surface of the water droplet, this is called surface tension. So the shape is spherical because a sphere has the least amount of surface area when comparing its volume to other shapes.

This paper concerns the measurement and prediction of rainfall noise with a particular focus on measurements made using the method described in the ISO rainfall noise standard. Rainfall noise is generated by rain impacting on a surface which excites the surface producing noise. Here, several different models for the force produced by a water droplet impacting on a flat inclined surface are presented. These models are designed for the nominal intense and heavy raindrops described in the ISO standard and are validated against experimental measurements. The best-performed models have been incorporated into theoretical methods for predicting the noise produced by rainfall on a flat inclined panel. These methods are used to produce noise level predictions for Introduction The forces produced when raindrops impact on a roof can be a significant source of noise, particularly for lightweight rooves [1]. The forces produced by the raindrop impacts induce vibration in the roof structure producing sound, which can be very disruptive to the occupants below if there is insufficient insulation. For this reason, standards for some buildings (e.g. school buildings in New Zealand and the UK [2], [3]) attempt to ensure that roof systems are constructed to produce rain noise of an acceptably low level. The rain noise produced by a roof system (or a component of a roof system – e.g. a skylight) can be assessed experimentally using the methods described in ISO 10140-5:2010/Amd.1:2014 [4] and A...

More • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • The correct option is B Surface tension The spherical shape of rain droplets is due to lowest surface tension of sphere. The lowest energy state of any liquid will be when its surface area is minimum. Hence it tries to decrease the surface area of the liquid to a minimum value. When a drop is formed, upward thrust due to surface tension balances the gravitational force. 2 π r γ = m g, where r and m are radius and mass of spherical droplet respectively and g is accelearation due to gravity.

A man stands by a stream holding a box. Animated flowers and plants sprout from the top. Wiggly arrows point up from the water and from the plants towards the sky. NARRATOR: Now, this is a familiar scene. The sun's heat causes water from plants, lakes and oceans to turn from a liquid to a vapour. Text on screen - 'Evapotranspiration.' NARRATOR: High in the atmosphere, the water vapour then cools down and condenses from a gas back into a liquid. Text on screen - 'Condensation.' Shot of clouds. Thunder rumbles and rain patters. A man in a business suit stands in the rain at a bus stop. Another man stands in a snow-covered field. Text on screen - 'Precipitation.' NARRATOR: The liquid water then falls back to the surface in the form of rain, snow, ice or hail. Water runs off into streams, lakes and oceans, or is stored in the ground or in snowpack. Text on screen - 'Runoff.' This is the water cycle, and it describes how our most vital resource moves through the whole Earth system. Text on screen - 'The Water Cycle.' Arrows forming a circle link pictures of evapotranspiration, condensation, precipitation and runoff together. NARRATOR: But like most things in our world, when we look at the tiny parts that make up the whole, we can learn a lot more about the phenomena. Animation of a circular ball of water in the air. NARRATOR: Take the shape of a single raindrop. Small droplets of water in the atmosphere are spherical in shape due to the surface tension, or skin, of the water mo...

Categories • • (31.9k) • (8.8k) • (764k) • (261k) • (257k) • (218k) • (248k) • (2.9k) • (5.2k) • (664) • (121k) • (72.1k) • (3.8k) • (19.6k) • (1.4k) • (14.2k) • (12.5k) • (9.3k) • (7.7k) • (3.9k) • (6.7k) • (63.8k) • (26.6k) • (23.7k) • (14.6k) • (25.7k) • (530) • (84) • (766) • (49.1k) • (63.8k) • (1.8k) • (59.3k) • (24.5k)