Democratic Republic of the CongoThe Democratic Republic of the Congo (DRC), also known as Congo-Kinshasa and formerly known as Zaire, is a country in Central Africa. By land area, the DRC is the second-largest country in Africa and the 11th-largest in the world. With a population of around 112 million, the Democratic Republic of the Congo is the most populous officially Francophone country in the world. The national capital and largest city is Kinshasa, which is also the economic center.
KinshasaKinshasa (kɪnˈʃɑːsə; kinʃasa; Kinsásá), formerly Léopoldville, is the capital and largest city of the Democratic Republic of the Congo. Once a site of fishing and trading villages situated along the Congo River, Kinshasa is now one of the world's fastest growing megacities. The city of Kinshasa is also one of the DRC's 26 provinces. Because the administrative boundaries of the city-province cover a vast area, over 90 per cent of the city-province's land is rural in nature, and the urban area occupies a small but expanding section on the western side.
Sine waveA sine wave, sinusoidal wave, or sinusoid is a mathematical curve defined in terms of the sine trigonometric function, of which it is the graph. It is a type of continuous wave and also a smooth periodic function. It occurs often in mathematics, as well as in physics, engineering, signal processing and many other fields. Its most basic form as a function of time (t) is: where: A, amplitude, the peak deviation of the function from zero. f, ordinary frequency, the number of oscillations (cycles) that occur each second of time.
Wave interferenceIn physics, interference is a phenomenon in which two coherent waves are combined by adding their intensities or displacements with due consideration for their phase difference. The resultant wave may have greater intensity (constructive interference) or lower amplitude (destructive interference) if the two waves are in phase or out of phase, respectively. Interference effects can be observed with all types of waves, for example, light, radio, acoustic, surface water waves, gravity waves, or matter waves as well as in loudspeakers as electrical waves.
