Examples of reflection. Plane wave, plane surface. The phase of the reflected sound waves from hard surfaces and the reflection of string waves from their ends determines whether the interference of the reflected and incident waves will be constructive or destructive.
The tendency to develop allergies is often hereditary, which means it can be passed down through genes from parents to their kids. But just because you, your partner, or one of your children might have allergies doesn't mean that all of your kids will definitely get them, too.
1 Some of the symptoms are similar to colds, such as sneezing, sore throat, coughing, runny nose, and congestion. 2  Sore throat in allergies is most often caused by postnasal drip. 3  Allergies can also cause rashes and itchy eyes.  Fevers and body aches are not signs of an allergy.