The pictures are not attached, therefore, I cannot give a specific choice.
However, I will try to help you out.
The angle of incidence is defined as the angle formed between the ray of light and the normal to the surface that the ray is falling on.
The angle of incidence can be shown in the attached image.
Therefore, for your question, choose the image on which the above description applies.
Hope this helps :)
Answer:
The electric field at x = 3L is 166.67 N/C
Solution:
As per the question:
The uniform line charge density on the x-axis for x, 0< x< L is 
Total charge, Q = 7 nC = 
At x = 2L,
Electric field, 
Coulomb constant, K = 
Now, we know that:

Also the line charge density:

Thus
Q = 
Now, for small element:


Integrating both the sides from x = L to x = 2L

![\vec{E_{2L}} = K\lambda[\frac{- 1}{x}]_{L}^{2L}] = K\frac{Q}{L}[frac{1}{2L}]](https://tex.z-dn.net/?f=%5Cvec%7BE_%7B2L%7D%7D%20%3D%20K%5Clambda%5B%5Cfrac%7B-%201%7D%7Bx%7D%5D_%7BL%7D%5E%7B2L%7D%5D%20%3D%20K%5Cfrac%7BQ%7D%7BL%7D%5Bfrac%7B1%7D%7B2L%7D%5D)
![\vec{E_{2L}} = (9\times 10^{9})\frac{7\times 10^{- 9}}{L}[frac{1}{2L}] = \frac{63}{L^{2}}](https://tex.z-dn.net/?f=%5Cvec%7BE_%7B2L%7D%7D%20%3D%20%289%5Ctimes%2010%5E%7B9%7D%29%5Cfrac%7B7%5Ctimes%2010%5E%7B-%209%7D%7D%7BL%7D%5Bfrac%7B1%7D%7B2L%7D%5D%20%3D%20%5Cfrac%7B63%7D%7BL%5E%7B2%7D%7D)
Similarly,
For the field in between the range 2L< x < 3L:

![\vec{E} = K\lambda[\frac{- 1}{x}]_{2L}^{3L}] = K\frac{Q}{L}[frac{1}{6L}]](https://tex.z-dn.net/?f=%5Cvec%7BE%7D%20%3D%20K%5Clambda%5B%5Cfrac%7B-%201%7D%7Bx%7D%5D_%7B2L%7D%5E%7B3L%7D%5D%20%3D%20K%5Cfrac%7BQ%7D%7BL%7D%5Bfrac%7B1%7D%7B6L%7D%5D)
![\vec{E} = (9\times 10^{9})\frac{7\times 10^{- 9}}{L}[frac{1}{6L}] = \frac{63}{6L^{2}}](https://tex.z-dn.net/?f=%5Cvec%7BE%7D%20%3D%20%289%5Ctimes%2010%5E%7B9%7D%29%5Cfrac%7B7%5Ctimes%2010%5E%7B-%209%7D%7D%7BL%7D%5Bfrac%7B1%7D%7B6L%7D%5D%20%3D%20%5Cfrac%7B63%7D%7B6L%5E%7B2%7D%7D)
Now,
If at x = 2L,

Then at x = 3L:

Answer:
The Roche limit for the Moon orbiting the Earth is 2.86 times radius of Earth
Explanation:
The nearest distance between the planet and its satellite at where the planets gravitational pull does not torn apart the planets satellite is known as Roche limit.
The relation to determine Roche limit is:
....(1)
Here
is radius of planet and
are density of planet and moon respectively.
According to the problem,
Density of Earth,
= 5.5 g/cm³
Density of Moon,
= 3.34 g/cm³
Consider
be the radius of the Earth.
Substitute the suitable values in the equation (1).
![Roche\ limit=2.423\times R_{E}\times\sqrt[3]{\frac{5.5 }{3.34 } }](https://tex.z-dn.net/?f=Roche%5C%20limit%3D2.423%5Ctimes%20R_%7BE%7D%5Ctimes%5Csqrt%5B3%5D%7B%5Cfrac%7B5.5%20%7D%7B3.34%20%7D%20%7D)

When the surface of a hard disk is scratched an some or all of the files are destroyed, it is called a head crash. It is a result of a disk in contact with the rotating platter causing it to permanently damage a very sensitive part of the disk.<span />
Answer:
<em>17 m/s west</em>
Explanation:
Runner 1 has velocity = 10 m/s west
runner 2 has velocity = 7 m/s east
From the frame of reference of runner 2, we can imagine runner 2 as standing still, and runner 1 moving away from him, towards the west with their combined velocity of
velocity = 10 m/s + 7 m/s = <em>17 m/s west</em>