storm cloud

Why are some clouds dark in appearance?

A cloud is a visible mass of water (tiny water droplets and/or ice crystals) suspended in the atmosphere at a considerable altitude. Clouds are usually white in appearance whereas others can appear grayish an...
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Is outer space a perfect vacuum?

Outer space (also called just space) is all the space in the universe beyond Earth and its atmosphere. It can be simple stated that in outer space there is no air (atmosphere) and it is a vacuum (empty ...
a star explosion

Is there sound in space?

This question may seems similar to a question already asked (Can you hear sound in space?) however, it is a very good question for the intellectually curious mind. So, is there sound in space? The answer is n...
Mariana trench location

How deep is the Ocean?

The world's deepest point in the oceans is the Challenger Deep which is found within the Marianas Trench. The Marianas Trench is a depression (deep cracks) in the floor of the western Pacific Ocean. Marianas ...
Water molecule

Where does the oxygen come from that fish breathe?

Water is formed from the combination reaction of hydrogen gas (H2) and oxygen gas (O2) to produce liquid water (H2O). In other words, each molecule of water is made up of two hydrogen atoms and one oxygen ato...
tooth eruption

Why do children loose their baby teeth?

Children usually start loosing their baby teeth (primary teeth) anywhere between the age of 6 to 7 years where their jaws have grown to its mature size. The reason for this is that the jaw of a baby is too sm...
blue sky1

Why is the sky blue in the day and black at night?

During the day (daylight) the sky has a blue appearance because the Sun’s light (white light) is made up of rainbow of colors (red, orange, yellow, green, blue, indigo and violet) of different wavelength....

What is the difference between an ocean and a sea?

Ocean and sea are two words that are used frequently and interchangeably (in writing and conversation) to mean the same thing: a continuous mass of seawater on the earth's surface. However, strictly speaking,...
why_burp

Why do people burp?

A burp (sometimes called a belch or by its medical term, eructation) is the release of gas from the digestive tract (in this case, theesophagus and stomach) through the mouth. It is part of the body natural c...

How does sound travel?

Sound is transmitted by particles (atoms or molecules) in a solid, liquid or gas colliding with each other. It is a wave which is created by vibrating objects and propagated through a medium (solid, liquid or...