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.
Symptoms & Types. Learn the types of allergies including food allergies, seasonal allergies, pet allergies, and many more. Respiratory Allergies. Spring Allergies There's no cure but you can take steps to curb springtime allergies, from medication to household habits. Summer Allergies Summer allergies are usually triggered by pollen from grasses and weeds. Fall Allergies Ragweed, mold and dust mites are the biggest allergy triggers in the fall. Winter Allergies If you have indoor allergies such as mold and dust mites, you may notice symptoms more during winter, when you spend more time inside. Hay Fever Hay fever, also known as allergic rhinitis, is an immune disorder characterized by an allergic response to pollen grains and other substances.