a. Use representations to describe a simple model for waves that includes how the amplitude of the wave is related to the energy in the wave.
Waves
A wave is a disturbance that transfers energy from on place to another. There are two ways in which wave can move. Longitudinal waves are waves that move in the same direction as the disturbance, while transverse waves move in the direction perpendicular to the disturbance. There are two types of waves, including mechanical waves and electromagnetic waves. Mechanical waves are waves that require a medium in order to travel, while electromagnetic waves do not require any form of matter to travel and is able to move across a vacuum.
Example - Sound is a longitudinal mechanical wave, since it moves in the direction of the disturbance, that is, the direction of the vibration, and it requires a medium in order to travel through. The sound that people hear are usually sound waves travel through air. |
Amplitude
Amplitude is the distance between a line through the middle of a wave and a crest or trough. A crest is the highest point, or the peak, of a wave. On the other hand, a trough is the lowest point, or valley, of a wave. It is possible to say that the amplitude of the wave is how large the wave is. The amplitude belongs to a wave is decided by the energy level of the wave. By increasing the energy of the wave, the amplitude of the wave increases.
Example - By making the sound waves energy increases, which make it louder, the amplitude, if being observed, will be bigger. |
b. Develop a model to describe that waves are reflected, absorbed, or transmitted through various materials.
Reflection
Reflection is the bouncing back of waves after it hits a barrier. Reflection is related to Newton's third law of Motion, which is, when a force is applied on an object, that object will released a force of equal size and opposite direction. The waves apply a force on the object it hit, therefore, the object returns an equal force, causing the wave to bounce back.
Example - Light is an electromagnetic wave. When it hits a mirror, the wave is reflected, and hit our eyes, allowing us to see the images in the mirror. |
Absorption
Absorption is the disappearance of electromagnetic wave into the medium. Absorption affects how things look, since it limits the light available to be reflected or transmitted. Opaque materials are materials that either absorbs or reflect light, but does not allow light to pass through. Light that is absorbed usually turn into some other kind of energy.
Example - Wood is an opaque material since it mainly absorbs light. Most of the visible light waves are absorbed by wood, while little of them are reflected, allowing us to see the wood. |
Transmission
Transmission is the passage of an electromagnetic wave through a medium. Transparent materials allow most of the light that strikes them pass through, but it can absorbs other electromagnetic wavelengths, but visible light is not affected, therefore move through. This allow human eyes to see through transparent materials.
Example - Glass, is a transparent material. It allows most of the visible light to pass through it, allowing us to see through the materials, but absorbs ultraviolet, a different type of electromagnetic wave that has a shorter wavelength with higher frequency. |