Explanation:
Given that,
The range of human hearing extends from approximately 20 Hz to 20 000 Hz. We need to find the wavelengths of these extremes when the speed of sound in air is equal to 338 m/s.
Speed of any wave is given by :

is wavelength of wave
If f = 20 Hz

If f = 20000 Hz

The smallest wavelength that can be heard is 0.0169 m and the longest wavelength that can be heard is 16.9 m.
Answer:
D) decreses the force .... so the guy can land safely :)
Explanation:
Answer: The correct answer is Diffraction.
Explanation:
Diffraction is the phenomenon in which a beam of light will get bend when it passes through a narrow aperture. It is accompanied by the interference between the wave form produced.
Consider a wave approaching a barrier with a small hole. The diffraction will occur when the wave passes through the hole. There is a bending of light as it passes through the edge of the object or through the hole.
The amount of bending light depends on the relative size of wavelength of the light in comparison to the size of the aperture.
Therefore, the correct answer is Diffraction.
Answer:
C.Vacuum
Explanation:
There are three methods of transfer of heat:
1) Conduction: conduction is the transfer of heat by direct contact between the molecules of two objects (or two substances). The particles of the hotter object vibrate faster than the particles of the colder object, so energy is transferred by collisions of the molecules from the hotter object to the colder object.
2) Convection: convection is the transfer of heat by mass movement of molecules. This occurs in fluids (liquids or gases), when an external source of heat is applied to the fluid. As a result, the part of the fluid closer to the source gets warmer, so it becomes less dense and rises, while the colder part sinks and replaces the hotter part, forming a convective current. The process continues until the heat source is removed.
3) Radiation: radiation is the transfer of heat carried by electromagnetic waves. Electromagnetic waves can travel in any medium and in a vacuum, so they are the only type of heat transfer that can occur in a vacuum (while conduction and convection cannot occur in a vacuum).
Erosion
Explanation:
The natural process that can most likely be reduced or prevented by this plant growth is erosion.
Erosion is the washing away of the top layer of the earth on which plant can grow.
- One of the ways of preventing or culling erosion is the planting of cover-crops that spreads out on the surfaces of the earth.
- These plant will prevent the collection and washing away of loose earth materials by the forces of erosion.
- Erosion occurs through three main agents which are wind, water and glacier.
- When the surface of the earth is properly covered, these agents will not have direct access/contact with the earth surface.
- The plant growth can cause the biological weathering of rocks through the penetrations of their root.
- But erosion is prevented by surface covering.
learn more:
Erosion brainly.com/question/2473244
#learnwithBrainly