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Physics 9th | Motion: Displacement
Motion: Displacement Motion 1. A body is said to be in motion if it changes its position with time with respect to the observer. e.g. When a tree T is observed by an observer A sitting on a bench, the tree is at rest. This is because the position of the tree is not changing…
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Frictional Electricity
Frictional Electricity: The word electricity is derived from the Greek word ‘electron’ which means amber. In the sixth century BC, a Greek philosopher Thales found that when a piece of amber (a kind of resin) is rubbed with fur, it acquires a remarkable property; it attracts small pieces of leaves, cork or dust. Today, we…