The movement of electrons The electrons are negatively (- ve) charged particles, They revolve around the nucleus with very high speed, The electron has a negligible mass relative to that of the proton or...
The reflection The reflection is the change in the direction of a wavefront at an interface between two different media so that the wavefront returns into the medium from which it originated such as...
The molecule The matter is composed of small building units called the molecules which are composed of tiny structural units called the atoms, and it is anything that has a mass and occupies space, The...
The reproduction process The reproduction process is a process that aims to secure the existence and continuity of living organisms species and to prevent them from the extinction, The human reproduce sexually when two...
