Which of the following is the best definition of constructive interference?
A)the subtraction of one wave from another
B) the addition of one wave to another
C)the blocking of one wave by another
D) the cancelling of one wave by another

Question

Which of the following is the best definition of constructive interference?
A)the subtraction of one wave from another 
  B) the addition of one wave to another 
   C)the blocking of one wave by another 
D)   the cancelling of one wave by another

anonymous · Answer

Think about construction, it makes things (bigger..!). Two waves can interfere (combine) if they are in the same vector space, and it will be constructive if they are in phase (peaks and troughs lined up). Does that help?