light scattering from a small particle giving the particle size refractive index and incident wavelength we have calculated the scattered intensity at different scattering angle from eq 2 11 for different u03bb the refractive index and size effects of the scattering of visible light can be easily evaluated from those equations fig1 is the calculated peak wavelength via particle size at the scattering angle 136 u00b0 using mie theory for white light even intensity of spectrum component from 400 nm to 700 nm incident upon a zinc oxide zno colloidal sphere fig1 shows that the scattered light prefers the blue green color for the particle size less than 500 nm actually for particle diameter less than 130 nm the shorter wavelengths are scattered most strongly which so called rayleigh scattering with the increase of particle sizes from 100 nm to 500 nm the scattering is dominated with mie scattering and the peak wavelength is shifted between green and violet due to resonance effect there is more than one peak in the wavelength range from 400 nm to 700 mm fig2 and fig3 show the normalized intensity at the angle 136 u00b0 near backward for even intensity light illuminating nanoparticles of diameter 175 nm and 430.