Answer:
n = 1.42
Explanation:
The refractive index for a medium is given by the ratio of the speed of light in vacuum to the speed of light in a medium.
![n=\dfrac{c}{v}\\\\n=\dfrac{3\times 10^8}{2.1\times 10^8}\\\\n = 1.42](https://tex.z-dn.net/?f=n%3D%5Cdfrac%7Bc%7D%7Bv%7D%5C%5C%5C%5Cn%3D%5Cdfrac%7B3%5Ctimes%2010%5E8%7D%7B2.1%5Ctimes%2010%5E8%7D%5C%5C%5C%5Cn%20%3D%201.42)
So, the refractive index of the medium is 1.42.
"Frequency" just means "often-ness" ... how often something happens.
It's always expressed as
<em>(number of happenings) / (some period of time) .</em>
First, find the amount of time for the dart to hit the board using this equation: t = d/v
t = 2 m/ 15 m/s = 0.133 s
Then, find the height the dart has fallen from its initial point using this equation: h = 0.5gt²
h = 0.5(9.81 m/s²)(0.133 s)² = 0.0872 m or 8.72 cm
Since the diameter of the bull's eye is only 5 cm, and you started at the same level of the top of the bull's eye, that means the maximum allowance would only be 5 cm. Since it exceeded to 8.72 cm, it means that <em>Veronica will not hit the bull's eye.</em>
Answer:
Radio waves
Explanation:
The electromagnetic spectrum includes all different types of waves, which are usually classified depending on their frequency. Ordering them from the highest frequency to the lowest frequency, they are:
- Gamma rays
- X-rays
- Ultraviolet
- Visible light
- Infrared radiation
- Microwaves
- Radio waves
Radio waves are the electromagnetic waves with lowest frequency, their frequency is lower than 300 GHz (
) and therefore they are the electromagnetic waves with lowest energy (in fact, the energy of an electromagnetic wave is proportional to its frequency). They are generally used for radio and telecommunications since this type of waves can travel up to long distances.