Nanometre facts for kids
The nanometre (symbol: nm) is a tiny unit of length in the metric system. It is used to measure things that are incredibly small. Imagine taking one metre and dividing it into a billion (1,000,000,000) equal parts. One of those tiny parts is a nanometre!
The word "nanometre" comes from two parts. "Nano-" is a prefix from Ancient Greek that means "dwarf" or "very small." The second part, "metre," also comes from Greek and means "unit of measurement." So, a nanometre literally means a "dwarf measurement." Scientists often write it as 1×10−9 m, which is a way to show how small it is using scientific notation.
Nanometres are perfect for measuring things that are too small to see, like atoms. They are also used to describe the wavelength of electromagnetic radiation, especially visible light. For example, the different colours we see in a rainbow have wavelengths between about 400 and 800 nanometres.
In the past, the nanometre was sometimes called the millimicrometre or millimicron. This was because it is one thousandth (1/1000) of a micrometre. Its old symbols were mµ or sometimes µµ.
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What is a Nanometre?
A nanometre is an extremely small unit of length. To give you an idea of its size, a human hair is about 80,000 to 100,000 nanometres thick! A single atom is usually less than one nanometre across. This shows just how tiny things measured in nanometres really are.
Measuring Tiny Things
Scientists and engineers use nanometres to measure and work with very small objects. This includes things like:
- The size of atoms and molecules.
- The tiny parts inside computer chips.
- The structures of new materials being created in nanotechnology.
Light and Wavelengths
The nanometre is also very important when talking about light and other types of electromagnetic radiation.
- Light travels in waves, and the distance between two peaks of a wave is called its wavelength.
- Different colours of visible light have different wavelengths, measured in nanometres. For example, blue light has a shorter wavelength (around 450 nm) than red light (around 700 nm).
- Beyond visible light, other forms of radiation like ultraviolet light and X-rays also have wavelengths measured in nanometres or even smaller units.
History of the Nanometre
The concept of measuring extremely small lengths has been around for a long time. As science and technology advanced, the need for precise units for tiny measurements grew. The nanometre became a standard unit because it fits perfectly into the SI system, which is used worldwide.
The older names like "millimicrometre" show how scientists tried to describe this tiny unit before the "nano-" prefix became widely adopted. The change to "nanometre" made the system simpler and more consistent.
Related pages
Images for kids
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This image shows a tiny carbon nanotube, which is a material often studied in nanotechnology. It was photographed using a special tool called a scanning tunneling microscope.
