Answer:
All of the following are true EXCEPT, the angle of refraction is 30 degrees
Explanation:
It is given that,
The index of refraction of the water is 1.33 and the angle of incidence is 30 degrees. We know that when a ray of white light moves through the air and strikes the surface of water in a beaker, refraction occurs. Let r is the angle of refraction. It can be calculated using Snell's law as :
![n=\dfrac{sin\ i}{sin\ r}](https://tex.z-dn.net/?f=n%3D%5Cdfrac%7Bsin%5C%20i%7D%7Bsin%5C%20r%7D)
![sin\ r=\dfrac{sin\ i}{n}](https://tex.z-dn.net/?f=sin%5C%20r%3D%5Cdfrac%7Bsin%5C%20i%7D%7Bn%7D)
![r=22.08^{\circ}](https://tex.z-dn.net/?f=r%3D22.08%5E%7B%5Ccirc%7D)
So, the angle of refraction is 22.08 degrees.
According to the law of reflection, the angle of incidence is equal to the angle of reflection. Since, it is incident at an angle of 30 degrees, so the angle of reflection will be 30 degrees. Also, total internal reflection will result, depending on the critical angle.
So, the wrong statement is the angle of refraction is 30 degrees. It is equal to 22.08 degrees.
The author's purpose is to persuade
(17.36 micron/30sec) x (1x 10⁻⁶ meter/micron) x (1km/1,000 m) x (3600 sec/hr) =
(17.36 x 10⁻⁶ x 3600) / (30 x 1000) km/hr =
<em>0.000 002 083 km/hr</em>
Answer:
8.9
Explanation:
We can start by calculating the initial elastic potential energy of the spring. This is given by:
(1)
where
k = 35.0 N/m is the initial spring constant
x = 0.375 m is the compression of the spring
Solving the equation,
![U=\frac{1}{2}(35.0)(0.375)^2=2.5 J](https://tex.z-dn.net/?f=U%3D%5Cfrac%7B1%7D%7B2%7D%2835.0%29%280.375%29%5E2%3D2.5%20J)
Later, the professor told the student that he needs an elastic potential energy of
U' = 22.0 J
to achieve his goal. Assuming that the compression of the spring will remain the same, this means that we can calculate the new spring constant that is needed to achieve this energy, by solving eq.(1) for k:
![k'=\frac{2U'}{x^2}=\frac{2(22.0)}{0.375^2}=313 N/m](https://tex.z-dn.net/?f=k%27%3D%5Cfrac%7B2U%27%7D%7Bx%5E2%7D%3D%5Cfrac%7B2%2822.0%29%7D%7B0.375%5E2%7D%3D313%20N%2Fm)
Therefore, Tom needs to increase the spring constant by a factor:
![\frac{k'}{k}=\frac{313}{35}=8.9](https://tex.z-dn.net/?f=%5Cfrac%7Bk%27%7D%7Bk%7D%3D%5Cfrac%7B313%7D%7B35%7D%3D8.9)