Author: Heba Soffar

The waves 0

The wave motion and the types of waves

The waves The wave motion is an example of the periodic motion. the wave is a disturbance that propagates and transfers the energy in the direction of the propagation, You notice that the concentric...

The dinosaurs extinction 0

The causes of the old and recent extinction

The scientists witnessed five mass extinctions, and some scientists believe that we live the sixth extinction age (The Recent Extinction), where the rate of the extinction is 40 times larger than the normal rate...