An achromatic combination of two prisms - one of quartz and other of flint glass is to be formed. If the refracting angle of the quartz prism is , find the refracting angle of the flint glass prism. Also find the net mean deviation produced by the combination. Given that for the flint glass :
and for the quartz glass :
.
-1.282
+1.282
-5.282
-8.282
For an achromatic combination, net dispersion
dispersion by one prism
dispersion by other prism.