PBXs (Private Branch Exchange) – telephone systems handling the external and internal calls of a company, building, etc. – have been used since the late 19th century. They allowed organizations to make internal calls without having to use the public [...]
Most of you have seen that when ever you see the images taken by astronauts or space telescopes from moon and from space there are no stars in the background! , The sky appears black and just the think shown there like earth, nebulas, galaxies are seen.
Do you wonder why it is? Continue reading to find answer.
Have you ever seen an strange scientific instrument and wondered for what is it used?
Scientific instruments looks as strange as the stuffs that can be done with them.
Here is a list of some popular scientific instrument , it’s image and it’s work.
Scientific instruments are mostly used to take measurements of some physical quantity , after all science is all about measurements.
There is a whole zoo of scientific instruments like Mobile phone , Computer , Rocket ; But what we are going to talk about here is the scientific instruments which are basically used to take scientific measurements.
Here is a list of some popular scientific instruments with their image and their use.
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