Three-point charges have equal magnitudes, two being positive and one negative. these charges are fixed to the corners of an equilateral triangle, as the drawing shows. the magnitude of each of the charges is 5.1 µc, and the lengths of the sides of the triangle are 2.2 cm. calculate the magnitude of the net force that each charge experiences.

Explanation:

q1 = - 5.1 micro coulomb

q2 = 5.1 micro coulomb

q3 =  5.1 micro coulomb

d = 2.2 cm

Let these charges are placed at A, B and C of the vertices of an equilaterla triangle

Force on A:

The net force acting on q1 is given by

F1 = 837.71 N

Force on B:

The net force acting on q1 is given by

F2 = 483.65 N

Force on C:

The net force acting on q1 is given by

F3 = 483.65 N

at positions a, g kinetic energy is maximum.

at position d, potential energy is maximum.

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.