Answer:
![F_0 = 393 N](https://tex.z-dn.net/?f=F_0%20%3D%20393%20N)
Explanation:
As we know that amplitude of forced oscillation is given as
![A = \frac{F_0}{ m(\omega^2 - \omega_0^2)}](https://tex.z-dn.net/?f=A%20%3D%20%5Cfrac%7BF_0%7D%7B%20m%28%5Comega%5E2%20-%20%5Comega_0%5E2%29%7D)
here we know that natural frequency of the oscillation is given as
![\omega_0 = \sqrt{\frac{k}{m}}](https://tex.z-dn.net/?f=%5Comega_0%20%3D%20%5Csqrt%7B%5Cfrac%7Bk%7D%7Bm%7D%7D)
here mass of the object is given as
![m = \frac{W}{g}](https://tex.z-dn.net/?f=m%20%3D%20%5Cfrac%7BW%7D%7Bg%7D)
![\omega_0 = \sqrt{\frac{220}{\frac{30}{9.81}}}](https://tex.z-dn.net/?f=%5Comega_0%20%3D%20%5Csqrt%7B%5Cfrac%7B220%7D%7B%5Cfrac%7B30%7D%7B9.81%7D%7D%7D)
![\omega_0 = 8.48 rad/s](https://tex.z-dn.net/?f=%5Comega_0%20%3D%208.48%20rad%2Fs)
angular frequency of applied force is given as
![\omega = 2\pi f](https://tex.z-dn.net/?f=%5Comega%20%3D%202%5Cpi%20f)
![\omega = 2\pi(10.5) = 65.97 rad/s](https://tex.z-dn.net/?f=%5Comega%20%3D%202%5Cpi%2810.5%29%20%3D%2065.97%20rad%2Fs)
now we have
![0.03 = \frac{F_0}{3.06(65.97^2 - 8.48^2)}](https://tex.z-dn.net/?f=0.03%20%3D%20%5Cfrac%7BF_0%7D%7B3.06%2865.97%5E2%20-%208.48%5E2%29%7D)
![F_0 = 393 N](https://tex.z-dn.net/?f=F_0%20%3D%20393%20N)
Answer:
From the formula of force:
![F = \frac{kAB}{ {r}^{2} } \\](https://tex.z-dn.net/?f=F%20%3D%20%20%5Cfrac%7BkAB%7D%7B%20%7Br%7D%5E%7B2%7D%20%7D%20%20%5C%5C%20)
since AB and k are constants:
![F \: \alpha \: \frac{1}{ {r}^{2} } \\ \\ F = \frac{x}{ {r}^{2} }](https://tex.z-dn.net/?f=F%20%5C%3A%20%20%5Calpha%20%20%5C%3A%20%20%5Cfrac%7B1%7D%7B%20%7Br%7D%5E%7B2%7D%20%7D%20%20%5C%5C%20%20%5C%5C%20F%20%3D%20%20%5Cfrac%7Bx%7D%7B%20%7Br%7D%5E%7B2%7D%20%7D%20)
x is a constant of proportionality
• when force is 4N, separation distance is 1
![4 = \frac{x}{1} \\ x = 4](https://tex.z-dn.net/?f=4%20%3D%20%20%5Cfrac%7Bx%7D%7B1%7D%20%20%5C%5C%20x%20%3D%204)
therefore, equation becomes
![F = \frac{4}{ {r}^{2} } \\](https://tex.z-dn.net/?f=F%20%3D%20%20%5Cfrac%7B4%7D%7B%20%7Br%7D%5E%7B2%7D%20%7D%20%20%5C%5C%20)
when r is doubled, r becomes 2. find F:
![F = \frac{4}{ {2}^{2} } \\ \\ F = \frac{4}{4} \\ \\ { \underline{force \: is \: 1N}}](https://tex.z-dn.net/?f=F%20%3D%20%20%5Cfrac%7B4%7D%7B%20%7B2%7D%5E%7B2%7D%20%7D%20%20%5C%5C%20%20%5C%5C%20F%20%3D%20%20%5Cfrac%7B4%7D%7B4%7D%20%20%5C%5C%20%20%5C%5C%20%7B%20%5Cunderline%7Bforce%20%5C%3A%20is%20%5C%3A%201N%7D%7D)
Answer: Alfred Wegener provided some of the important points that supported the theory of continental drift. They are as follows-
- The continents were once all attached together, and this can be proved by studying the coastlines of some of the continents that perfectly matches with one another.
- The appearance of similar rock types and similar fossils (including both animals and plants) has also contributed much information that continents were once all together.
The electromagnetic spectrum includes a continuous spectrum of wavelengths that include:
Radio waves, microwaves, infrared light, visible, ultraviolet, X-rays, gamma rays
The wavelength decreases from radio waves to gamma rays, whereas the energy increases along the same direction.
In the given example, radio waves have a lower energy and higher wavelength than visible light. The latter can be perceived by the human eye, whereas radio waves are not visible to the human eye.
1) They have colors = visible light
2) They can travel in a vacuum = both
3) They have energy = both
4) They’re used to learn about dust and gas clouds = radio waves
5) They’re used to find the temperature of stars = visible light
6)They’re invisible = radio waves