My Science School

An accessory cloud is a cloud which is dependent on a larger cloud system for its development and continuance. It is often an appendage but also can be adjacent to the parent cloud system.

The arcus and roll clouds, shelf cloud, wall cloud, and scud are examples of low level or vertical accessory clouds whilst the anvil, and overshooting top, are examples of high level accessory clouds. The condensation funnel of funnel clouds and tornadoes are also accessory clouds. They are associated with deep moist convection and especially cumulonimbus, the primary cloud producing thunderstorms. The pileus and mammatus types can form at various altitude ranges depending on the main clouds with which they are associated. The World Meteorological Organization classifies most accessory clouds as supplementary features. The height range classification of a supplementary feature is the same as the parent cloud. As an example, the anvil cloud (supplementary feature incus) forms at high altitude but is not classified by the WMO as a high cloud because of its association with the genus cumulonimbus.

It is very rare for any accessory cloud to generate its own precipitation. However, the parent cloud may generate precipitation. Precipitation from the parent cloud is often confused with the accessory cloud and observers think that the precipitation is actually falling from the accessory cloud.

Picture Credit : Google

The classification of clouds into types was first proposed by Luke Howard in 1802 and we largely use the same system today. This splits clouds into three main types - stratus, cumulus and cirrus.

Clouds are continually changing and appear in an infinite variety of forms. The classification of clouds is based on a book written by Luke Howard, a London pharmacist and amateur meteorologist, in 1803. His book, The Modifications of Clouds, named the various cloud structures he had studied. The terms he used were readily accepted by the meteorological community and are still used across the world today.

The World Meteorological Organization (WMO) has extended Luke Howard's classifications to make 10 main groups of clouds, called genera. These are divided into three levels - cloud low (CL), cloud medium (CM) and cloud high (CH) - according to the part of the atmosphere in which they are usually found.

Credit : Met Office

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Max Planck was a German theoretical physicist who won the Nobel Prize for Physics in 1918 for his work on the quantum theory, which revolutionised human understanding of atomic and subatomic processes.

Max Karl Ernst Ludwig Planck was born in Kiel, Germany, to Julius Wilhelm and Emma Planck. Planck studied physics at the Universities of Munich and Berlin, and received his doctorate of philosophy at Munich in 1879 after completing his paper detailing his research and theory of thermodynamics, an interest he acquired from his studies under physicist Gustav Robert Kirchhoff, whom he greatly admired. His dissertation in the second law of thermodynamics laid the ground for his future researches, which eventually led him to discover the quantum of action, now known as Planck's constant h.

In 1885, the University of Kiel appointed Planck as associate professor of theoretical physics. In 1892, he became a professor at the University of Berlin.

In 1894, he turned his attention to the problem of black-body radiation. In 1859-60 Kirchhoff had defined a black body as an emitter and absorber of radiation. But there was a mismatch between the wavelengths radiated by black body and the wavelengths predicted by classical theories of thermodynamics. When a black body is heated, electromagnetic radiation is emitted with a spectrum corresponding to the temperature of the body, and not to its composition. This led Planck to propose the concept of quanta. In 1900, he suggested that light and other electromagnetic waves were emitted in discrete units of energy, which he called "quanta" (multiples of a certain constant. which now bears the name "Planck's constant). The discovery of Planck's constant enabled him to define a new universal set of physical units such as the Planck length and the Planck mass. Planck's concept of energy quanta was accepted only years later but is considered one of the scientific breakthroughs that most contributed to modern physics. During World War Two, his home was completely destroyed by bombings in 1944 and he lost all of his papers. Did you know Max Planck was talented musically? He composed classical music and played the cello and the piano.

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What you need:

Three small balloons, three packets of yeast (from a grocery store), sugar, warm water, three one-litre plastic bottles

What to do:

1. Fill up each bottle with about one inch of very warm water.

2. Put one packet of yeast into each bottle.

3. Now, in the first bottle, put one teaspoon of sugar in the second one, put two teaspoons and three teaspoons in the third.

4. Cap all the bottles and shake them well.

5. Open the caps and put the three balloons on the bottles necks. Leave the bottles undisturbed for a couple of hours.

What happens:

The balloons begin to inflate in a while. The bottle with the maximum amount of sugar has the most inflated balloon.

Why?

Yeasts are nothing but a kind of microorganism. They like to feed on sugar. Which is why they're used mostly in baking. Yeasts require warmth and moisture to become active which is why you need the warm water.

When yeasts begin to feed on sugar, carbon dioxide gas is released. This gas fills the bottle and then inflates the balloon. The more sugar the yeasts get to eat, the more gas they release and the more the balloon inflates. Yum.

Picture Credit : Google

What you need:

A plate, a glass jar with a broad mouth, a tissue, a piece of paper, water and a matchbox

What to do:

1. Make the tissue paper wet and lay it out on the plate. The tissue should be broader than the mouth of the glass jar.

2. Cut the paper into a strip the size of a sticky note.

3. With an adults help, set one end of the paper on fire and drop it in the glass jar.

4. Check that the paper is burning well inside the jar and then quickly invert the jar over the wet tissue on the plate.

5. Let the paper bum and go out. Once that happens, try to lift the jar.

What happens:

The entire plate comes away with the glass jar

Why?

The burning strip of paper heats the air inside the jar, causing it to expand and leave the jar. When you invert the jar on the plate, and the paper goes out the air inside the jar cools and contracts, causing the air pressure to fall. Normally, air from the outside would rush in to fill the extra space left by the contracting air. But the plate and the wet tissue are in the way this time. So there's a low air pressure zone inside the jar while the air pressure outside it is higher. Due to this pressure difference the air pressure outside pushes the plate against the jar, causing the two to stick. They remain like this as long as the tissue is wet, because the wet tissue essentially acts as a seal that doesn't allow air to pass. However, once the tissue dries... crash!

Picture Credit : Google

What you need:

A lemon, strips of zinc and copper,

What you do:

• Roll the lemon to make it juicy inside.
• Stick a strip of zinc and a strip of copper into the lemon leaving one end of each strip sticking out. The two strips should not touch each other inside the lemon.
• Now touch both the strips at the same time with your tongue.

What you experience:

A tingling sensation.

Why?

 It's because you've turned the lemon into an electric cell!

An electric cell in its most simple form is composed of two strips of different metals and a chemical called an electrolyte which conducts the current in the case of the lemon, its juice is the electrolyte.

Picture Credit : Google

What you need:

An empty aluminium can, water, a bowl, tongs, a stove with a pan on it

What to do:

1. First, wash the soda can so it is free from any residues.

2. Fill the bowl with cold water, the colder the better. Ice water works too. Keep the bowl aside.

3. Put some water in the aluminium can. It can be about a tablespoon, just enough to cover the bottom of the can.

4. Light the stove and place the aluminium can on the pan.

5. Let the water inside the can heat and bubble up. When you see water vapour escaping from the can's mouth, pick up the can using the tongs.

6. Quickly (and carefully!) invert the can and immerse it in the cold water.

What happens:

The can gets crushed!

Why?

Initially, the can is full of air and some water. When you heat it, the water boils and changes into gas, i.e. water vapour. This vapour pushes out the air that was originally inside the can as it expands.

When you turn the can upside down in the water, in effect, you close the mouth of the can. No more air can enter into it.

The cold water in the bowl causes the can to cool down, and the water vapour in it as well. As the water vapour cools, it contracts. So, it no longer occupies the entire space of the can. This contraction creates a low pressure zone inside the can. Ordinarily, air from outside would rush in and equalize this pressure, but thanks to the can being upside down in water, that cannot happen.

In this case, the pressure that the outside air exerts becomes so strong that it crushes the can! The contracting water vapour inside cannot exert enough pressure on the inside walls to help the can retain its shape.

Picture Credit : Google

Saturn has 82 moons. Fifty-three moons are confirmed and named and another 29 moons are awaiting confirmation of discovery and official naming. Saturn's moons range in size from larger than the planet Mercury — the giant moon Titan — to as small as a sports arena. 

Most of these moons are small, icy bodies that are little more than parts of its impressive ring system. In fact, 34 of the moons that have been named are less than 10 km in diameter while another 14 are 10 to 50 km in diameter. However, some of its inner and outer moons are among the largest and most dramatic in the Solar System, measuring between 250 and 5000 km in diameter and housing some of greatest mysteries in the Solar System.

Saturn’s moons have such a variety of environments between them that you’d be forgiven for wanting to spend an entire mission just looking at its satellites. From the orange and hazy Titan to the icy plumes emanating from Enceladus, studying Saturn’s system gives us plenty of things to think about. Not only that, the moon discoveries keep on coming. As of April 2014, there are 62 known satellites of Saturn (excluding its spectacular rings, of course). Fifty-three of those worlds are named.

Credit : Universe Today

Picture Credit : Google