<P> The deviation angle in a prism depends upon: </P> <P> Refractive index of the prism: The refractive index depends on the material and the wavelength of the light . The larger the refractive index, the larger the deviation angle . </P> <P> Angle of the prism: The larger the prism angle, the larger the deviation angle . </P> <P> Angle of incidence: The deviation angle depends on the angle that the beam enters the object, called angle of incidence . The deviation angle first decreases with increasing incidence angle, and then it increases . </P>

If d is decreases the angle of deflection