QA › Physics › Which of the following describes a condition in which an individual would not hear an echo?

Which of the following describes a condition in which an individual would not hear an echo?

A. An individual is standing 30 meters in front of the reflecting surface.

B. An individual is standing in the range of the sound waves coming from the original sound source as well as the reflected waves.

C. A sound wave reaches the ear and the reflected wave reaches the ear less than 0.1 second later.

D. The reflecting source is approximately 21.5 meters from the individual.

Answer: C. A sound wave reaches the ear and the reflected wave reaches the ear less than 0.1 second later.

Echoes are reflected sound waves, and they can be heard from a distance, provided that distance is not less than 17 meters, which disqualifies options A and D. If an individual is standing in the range of the sound waves coming from both the original source and the reflected waves, then they will definitely hear an echo. If however, sound waves reach the ear less than 0.1 seconds after the sound is made, then the ear will interpret it as a part of the original sound, and they will not hear an echo.

Physics

3 years ago

147 Views

Math Calculus — AID—

Total time spent: 4 hours 15 minutes (it is equivalent to 255 minutes). Let the flight time from Paris to Glasgow be X. Then the flight time from Glasgow to Paris will be (X+10). We have an equation with one unknown variable: X + 45 + (X+10) = 255 ⇒ X = 100 So the […]

What were the typical crafts for Maya?

Mayans are well-known as great pottery makers. They did not use the pottery wheel. However,the tecnique they used was coiling consecutive rings of clay on top of each other and smoothing the surface by hand. Also, they were good when it came to working with stone – stone craving is another important craft of Maya. Many […]

What defines a free market?

The efficient working of a free market economy requires that the producer firms must have incentives to work hard and produce goods and services at the lowest possible cost per unit of output Market economies provide incentives to the firms and individuals by recognising and enforcing the property rights of the individuals and firms to […]

How does 3D printing work?

There are three different ways 3D printers work but they all rely on the printer converting a design into individual 2D slices which are then combined to make the final 3D object. The first method uses a pool of chemicals that turns solid when light, typically a UV laser, is shone on to it. The […]

Cigarette smoking causes emphysema.

Nearly everyone knows that smoking causes lung cancer, but did you know that smoking causes a number of other serious lung diseases? These include chronic bronchitis and emphysema, collectively known as chronic obstructive pulmonary disease (COPD). COPD is the fourth largest killer of Australians and smoking is the most important risk factor for COPD. When […]