# Prism deviations isaac physics

I am struggling to complete this question. I got part a), but for part b), I am unsure as to how to use the refractive indices of red light and blue light. Should I maybe draw the path for red light? and then blue light? Somehow I should equate the deviation angles. This is the question: https://isaacphysics.org/questions/prism_deviations_sym?board=81924f4f-566c-4208-a960-534fc43c0637&stage=all
Help would be much appreciated.
You just use the result from part a and have to factor in that the deflection for the second prism is negative, while the deflection for the first prism is negative.

You should end up with the equation beta( r1..) - gamma (r2..) = beta(b1..) - gamma(b2...)
where r1.. r2.. b1.. b2.. are the respective equations that you use from part a.
Original post by mosaurlodon
You just use the result from part a and have to factor in that the deflection for the second prism is negative, while the deflection for the first prism is negative.
You should end up with the equation beta( r1..) - gamma (r2..) = beta(b1..) - gamma(b2...)
where r1.. r2.. b1.. b2.. are the respective equations that you use from part a.

thanks for the help!!