Determine la velocidad media de un móvil que lleva una velocidad inicial de 3m/s y su velocidad final es de 4.2m/s

3.6 m/s

Step-by-Step

Translated from Spanish to English for other English speaking students to benefit.

Question:

Determine the average speed of a mobile that has an initial speed of 3m/s and its final speed is 4.2m/s

To average anything, just put them into a fraction and divide their total by the number of things you want to average.

En español

Para promediar cualquier cosa, solo póngalos en una fracción y divida su total por la cantidad de cosas que desea promediar.

Porque hay  2 velocidades, y queremos promediarlas, dividimos su total por 2.

scattering of light by tiny particles in air to produce the colors we see on sky, is dependent on the following factors:

(i) wavelength of light

(ii) size of the scattering particle  

(iii) distance traveled by light through the atmosphere.

according to rayleigh's law of scattering, the amount of scattering is inversely proportional to the fourth power of its wavelength. shorter the wavelength, greater is its scattering. hence violet/blue light is scattered more than red.

sun's light is a composite light ( visible light) with wavelengths in the range 400 nm (violet) to 700 nm (red). as sunlight passes through our atmosphere, the molecules of air scatter light according to their wavelengths. during sunrise and sunset, the sun's position is below the horizon. hence light from the sun travels a greater distance in the atmosphere when compared to its position a noon.

as sunlight enters the earth's atmosphere, blue light is scattered away and at the end of its journey in the sky, only red and orange wavelengths remain in the beam.

hence at sunrise and sunset, the sky appears reddish orange.

wavelength divides in half and speed stays the same.