Two identical waves undergo pure constructive interference. How is the resultant intensity related to that of the individual waves?

A. resultant intensity is half of wave intensity

B. resultant intensity is same as individual wave intensity

C. resultant intensity is double individual wave intensity incorrect

D. resultant intensity is quadruple individual wave intensity

I said double because it's constructive interference, but that was wrong. What should it be and why?

I'm in an online class and material about constructive interference and intensity wasn't covered before this question......

1 answer

amplitude is double, so intensity is ...? http://www.schoolphysics.co.uk/age16-19/Wave%20properties/Wave%20properties/text/Intensity_and_amplitude/index.html