How are Tides Formed?

Tides:

Tides are the regular rise and fall of sea levels caused by the gravitational forces exerted by the Moon and the Sun, as well as the rotation of the Earth.

The Basics of Tides:

Gravitational Pull: The Moon’s gravity pulls on the Earth's water, creating a bulge of water on the side of the Earth facing the Moon. This bulge is the high tide.

Centrifugal Force: As the Earth and the Moon orbit around a common center of mass, a centrifugal force is generated. This force causes another bulge on the opposite side of the Earth, creating a second high tide.

Types of Tides:

High Tide: Occurs where the water is bulging due to the gravitational pull of the Moon and the centrifugal force.

Low Tide: Occurs in areas between the high tides, where the water level is lower.

The Role of the Sun:

The Sun also exerts a gravitational pull on the Earth's waters, but it is less significant than the Moon's pull because the Sun is much farther away. However, the Sun's gravity can either enhance or diminish the effects of the Moon's gravity:

Spring Tides: When the Sun, Moon, and Earth are aligned (during full moon and new moon), their combined gravitational forces create higher high tides and lower low tides. These are known as spring tides.

Neap Tides: When the Sun and Moon are at right angles to each other (during the first and third quarters of the moon), their gravitational forces partially cancel each other out, resulting in lower high tides and higher low tides. These are called neap tides.

The Tidal Cycle:

Semi-Diurnal Tides: Most coastal areas experience two high tides and two low tides every 24 hours and 50 minutes. This is because it takes about 24 hours and 50 minutes for the Earth to complete one rotation relative to the Moon.

Diurnal Tides: Some areas experience only one high tide and one low tide each day.

Mixed Tides: In some locations, there are two high tides and two low tides of different heights each day.

Factors Affecting Tides:

The Shape of the Coastline: Coastal shapes can influence how high or low tides are. Narrow bays, inlets, and estuaries can experience much higher tides than more open coastlines.

Ocean Basin Topography: The depth and shape of the ocean floor can affect tidal ranges. Shallow areas can amplify the effects of tides.

Earth’s Rotation: The rotation of the Earth also affects the timing and height of tides, creating complex tidal patterns.

Tidal Effects and Uses:

Intertidal Zones: The area between high and low tide marks is called the intertidal zone. This area is rich in marine life and is crucial for many ecosystems.

Tidal Energy: Tides can be harnessed to generate renewable energy. Tidal power plants use the movement of water caused by tides to produce electricity.

Navigation and Fishing: Knowledge of tides is essential for navigation and fishing. Ships must account for tides when entering and leaving harbours, and many marine species rely on tidal cycles for breeding and feeding.

Tides are a fascinating natural phenomenon influenced by the gravitational pull of the Moon and the Sun, the rotation of the Earth, and the shape of coastlines and ocean basins. They play a crucial role in marine ecosystems, human activities, and even renewable energy. Understanding tides helps us appreciate the intricate connections between celestial bodies and our planet’s oceans! 

The Photoelectric Effect.

    A process known as the photoelectric effect occurs when a substance, usually a metal, absorbs enough light to cause electrons to be expelled from its surface. This phenomenon made a fundamental contribution to the advancement of contemporary physics and offered vital data in support of the quantum theory of light. 

Scientific Principles:

Photon Concept:

• Light consists of particles called photons, each carrying a discrete amount of energy determined by its frequency (E=hv), where "h" is Planck's constant and "v" is the frequency of the light.

Energy Threshold:

• For electrons to be ejected from a material, the energy of the incident photons must exceed a certain minimum value known as the work function (ϕ) of the material.

Electron Emission:

• When a photon hits the material, its energy is transferred to an electron. If the energy is greater than the work function, the electron is emitted from the surface with kinetic energy given by Ek=hv−ϕ.

Intensity Independence:

• The number of ejected electrons depends on the intensity of the light, but the energy of the ejected electrons depends only on the frequency of the incident light.

Historical Development

Heinrich Hertz (1887):

    While researching electromagnetic waves, the photoelectric effect was discovered. Hertz noted that sparks may jump across metal electrodes more readily in the presence of UV light, but he did not investigate the underlying mechanism.

Wilhelm Hallwachs (1888):

    It was discovered that a negatively charged zinc plate would lose its charge when light fell on it, offering preliminary proof for the photoelectric effect.

J.J Thomson (1899):

    Photoelectrically released electrons' charge-to-mass ratio was measured, and it was determined that these particles were identical to those seen in cathode rays.

Albert Einstein (1905):

    Used the quantum theory to provide a theoretical justification for the photoelectric effect. According to Einstein's theory, the energy of the quanta—later referred to as photons—in light is proportional to the frequency of the light. He was awarded the 1921 Nobel Prize in Physics for this achievement.

Robert Millikan (1916):

    Millikan's work, which involved precise tests to validate Einstein's theory, cleared the air for the linear relationship between the frequency of incident light and the kinetic energy of released electrons. Millikan was first sceptical of the hypothesis.

Impacts:

Quantum Theory of Light

    The photoelectric effect provided evidence in favour of the fundamental tenet of quantum mechanics—that light possesses both wave and particle characteristics.

Useful Applications:

   Numerous technologies, such as photovoltaic cells (solar panels), photomultiplier tubes, and photoelectron spectroscopy, rely on the principles underlying the photoelectric effect.

   One of the key ideas in comprehending how light and matter interact, bridging the gap between classical and quantum physics, is the photoelectric effect. 

The Brief History of The Sun.

The Sun:

The Sun is the star at the centre of our solar system. Its gravity holds the solar system together, keeping everything from the - biggest planets to the smallest bits of debris - in its orbit.

Heat and light are produced by nuclear events that occur deep beneath. In order to produce this energy, The Sun has been using four million tonnes of hydrogen fuel each second since its formation, or around 4.6 billion years ago.

Solar Flares:

A solar flare is a massive eruption that occurs on the Sun when energy that has been trapped in "twisted" magnetic fields- which are typically found above sunspots, Chromosphere -is suddenly released.

They may heat materials to millions of degrees in a matter of minutes, resulting in a burst of radiation that includes: radio waves, X-rays, and gamma rays.

Sun Spots:

Sunspots are areas where the magnetic field is about 2,500 times stronger than Earth's, much higher than anywhere else on the Sun. Because of the strong magnetic field, the magnetic pressure increases while the surrounding atmospheric pressure decreases.

This in turn lowers the temperature relative to its surroundings because the concentrated magnetic field inhibits the flow of hot, new gas from the Sun's interior to the surface.

Sunspots tends to occur in pairs that have magnetic fields pointing in opposite directions.

Why Sun Spots are Dark?

The sunspots are large concentrations of strong magnetic field. Some energy is partially prevented from passing through the surface by this magnetic field.

As a result, sunspots experience a lower surface temperature than other areas of the surface. It appears darker when the temperature is lower.

Coronal Mass Ejections (CMEs):

Coronal mass ejections (CMEs) are large expulsions of plasma and magnetic field from the sun's atmosphere the corona.

Compared to solar flares bursts of electromagnetic radiation that travel at the speed of light, reaching Earth in just over 8 minutes.

Formation of CMEs:

The more explosive CMES generally begin when highly twisted magnetic field structures (flux ropes) contained in the Sun's lower corona become too stressed and realign into a less tense configuration - a process called magnetic reconnection.

Near Earth CMEs Effects:

Auroras:

The CMEs causes stunning light displays known as auroras, visible in the polar regions of the earth.

Geomagnetic Storms:

CMEs can cause significant disturbances in Earth's magnetosphere, leading to geomagnetic storms which are; Satellite Operations, Power Grids, Communication Systems.

Radiation Hazards:

It Increases radiation levels at high altitudes, especially near the poles.

Preventing & Monitoring:

SPACE WEATHER FORECASTING:

To provide early alerts of possible CMEs, organisations such as NASA and NOAA's Space Weather Prediction Centre (SWPC) track solar activity.

AID:

Continuous monitoring and improved prediction models are essential to prevent the bad impacts of CMEs.

How to Find the Sun Spots Area:

To find the area of sunspots, I use the manual formula to calculate the area of the sunspots.

As = ((Af x n) / cos (B) x cos (L))

Where,

As - Area of the sunspot,

Af - Area factor constant for the solar chart image (i.e., 63.66),

n - Number of grid sares occupying the sunspot,

B- Heliographic latitude,

L - Angular distance of the sunspot from the solar disk centre.

The physical unit for the calculated area is a millionth of a hemisphere (MHS). 

Solar Cycle:

About every 11 years, the Sun's magnetic field gradually changes polarity, a process known as the solar cycle. This reversal causes changes in solar activity.

The solar cycle has been observed and recorded since the mid-18th century, with the current cycle being Solar Cycle 25. 

 "Sun, in fact, is the center of the universe" -Nicolaus Copernicus. 

History of Cinema: Beyond Screens.

Cinema is the most widely acclaimed means of entertainment in the world today. It is a combination of various equipments, techniques and art which constitutes cinema. But the most important things needed to experience cinema are camera, film reel and a projector. "Wheel of life' or 'zoopraxiscope' was the first machine to show animated pictures. It was patented in 1867 by William Lincoln. In a zoopraxiscope, moving photographs were watched through a slit. 

Zoopraxiscope

"The cinema is an invention without a future." - Louis Lumière. The Lumiere brothers-Auguste and Louise - are credited for inventing the first motion picture camera in the year, 1895. But even prior to Lumiere brothers, many others had made similar inventions. Lumiere brothers  invented a portable motion-picture camera, film processing unit and a projector called the Cinematographe. Here, three functions were covered in one invention. 

Lumiere Brothers

Cinematographe

The first footage shot by Lumiere brothers was that of workers leaving the Lumiere factory.

Cinematographe or Cinematography brought a revolutionary change in the world of cinema and made motion pictures popular. Though, prior in 1891, the Edison Company came up with a kinetoscope which allowed to watch cinema one person at a time, Edison's vitascope (1896) was the first commercially successful projector in USA. 

Kinetoscope

A camera shoots an activity on a film roll, also known as a film negative. This film negative is then edited. An editor removes away unnecessary scenes by cutting away that portion of the film role. Then the edited film roll is processed in a lab with required effects. The final film footage is then mounted on a projector. A projector is a device which projects the film running on the film roll on a blank white screen with the help of light. There are two pulleys on a projector. The film reel is mounted on the first projector and is run through the first to the second projector with the help of a motor. 

Advertising of Edson's  Vitascope

The film reel passes between a magnifying lens and a light bulb. The lens increases the size of the image on the blank white screen.

Cinematography is an art form unique to motion pictures. Although the exposing of images on light-sensitive elements dates back to the early 19th century, motion pictures demanded a new form of photography and new aesthetic techniques. In the infancy of motion pictures, the cinematographer was usually also the director and the person physically handling the camera. As the art form and technology evolved, a separation between the director and the camera operator emerged. With the advent of artificial lighting and faster (more light sensitive) film stocks, in addition to technological advancements in optics and new techniques such as colour film and widescreen, the technical aspects of cinematography necessitated a specialist in that area. 

It was a key during the silent movie era no sound apart from background music, no dialogue the films depended on lighting, acting and set. 

In 1919, in Hollywood, the new motion picture capital of the world, one of the first (and still existing) trade societies was formed: the American Society of Cinematographers (ASC), which stood to recognise the cinematographer's contribution to the art and science of motion picture making. 

Films are made up of a series of individual images called frames. When these images are shown rapidly in succession, a viewer has the illusion that motion is occurring. The viewer cannot see the flickering between frames due to an effect known as persistence of vision, whereby the eye retains a visual image for a fraction of a second after the source has been removed. Viewers perceive motion due to a psychological effect called the beta movement. 

 

A Film Projector

CINEMA 4D is a 3D modelling, animation and rendering application developed by MAXON Computer GmbH of Friedrichsdorf, Germany. It is capable of procedural and polygonal/subd modelling, animating, lighting, texturing, rendering and common features found in 3d modelling applications.  

"IF A MILLION PEOPLE SEE MY MOVIE, I HOPE THEY SEE A MILLION DIFFERENT MOVIES."            ---QUENTIN TARANTINO--- 

QUENTIN TARANTINO. 

What are Infra-red Radiations?

We all know that the sunlight consists of all those colours which are seen in a rainbow. These colours are: violet, indigo, blue, green, yellow, orange and red. Light from the sun travels in the form of waves which are known as electromagnetic waves. The different colours of light have different wavelengths. Our eyes are sensitive only to the wavelengths relating to the above seven colours. Apart from the wavelengths of these seven colours, the sunlight consists of radiations of other wavelengths also, but our eyes are not sensitive to them. Rays having wavelengths higher than that of red light are called infra-red rays and those lower than violet light are called ultraviolet rays. Both infra-red and ultraviolet rays are not visible to our eyes.

Spectral Lines.

Infra-red rays come not only from the sun but from every hot object. Burning wood and coal, electric heater-all produce these rays. These can be recorded on special type of photographic films made of infra-red sensitive materials. Whenever these rays fall on any material body they produce heat. They are very useful to us. 

Wavelength 

Wavelength of Infrared Radiation.

Infra-red radiations are being used for the treatment of several diseases. Special types of infra-red lamps are used for treating the pains of muscles and joints-especially for backpain. They are also used for heating rooms in winter.

Animals Pictures taken under IR Camera.

Infra-red radiations are being used for the guidance and control of missiles and other ballistic weapons. These radiations are also used for transmitting and receiving invisible signals. Molecular structures are studied with the help of these radiations. Impurities present in the materials can also be detected by these rays. 

Light, The Visible Reminder of Invisible Light ---John Green--- 

 Why Does Milk Appear in White Colour?  

Milk and curd looks white when we seen in the sunlight but they appears red in red light and blue in blue light. Have you ever wondered? Why its happens? If you don't know follow my blog page for more curious science thoughts. 

We all know that the sunlight is a mixture of seven colours. There are:  Violet, Indigo, Blue, Green, Yellow, Orange & Red. The colours of the sun light can be separated with the help of a prism. The coloured an object depends upon the colour that reaches our eyes after reflection from the object. 

Colour of an objects depends upon the reflected light. 

 

What ever colour is reflected by the object, is the colour of the that object. The molecular structure of milk and curd is such that they do not absorb any of the colours of the sunlight but reflected all of them, Thus these substances appear white. When milk and curd are viewed in red light, they look red because red colour is reflected by them. The same argument holds good for the colours of the other objects also. 

Colors! What A Deep And Mysterious Language, The Language Of Dreams.   -Paul Gauguin.