Complete Question
The complete question is shown on the first uploaded image
Answer:
a it is always zero
b 0
c ![\eta = -\epsilon _o E](https://tex.z-dn.net/?f=%5Ceta%20%20%3D%20%20-%5Cepsilon%20_o%20E)
Explanation:ss
Here the net charge is on the outer surface of the conductor thus this means that the net charge inside the conductor is zero
Generally the charge density of a conductor is dependent on the charge per unit area which implies that the charge density is dependent on the net charge so this means that the charge density inside the conductor is zero
Generally the direction of electric field this from the positive charge to the negative charge so from the question we can deduce that the negative charge is located on the surface of the conductor
So We can mathematically define the charge density on the surface of the electric field as
∮![E \cdot dA = \frac{-Q}{\epsilon _o}](https://tex.z-dn.net/?f=E%20%5Ccdot%20dA%20%3D%20%20%5Cfrac%7B-Q%7D%7B%5Cepsilon%20_o%7D)
Where E is the electric field
change in unit area
is the negative charge
is the permittivity of free space
So
![EA = \frac{-Q}{\epsilon _o }](https://tex.z-dn.net/?f=EA%20%20%3D%20%20%5Cfrac%7B-Q%7D%7B%5Cepsilon%20_o%20%7D)
![\frac{Q}{A} = -\epsilon _o E](https://tex.z-dn.net/?f=%5Cfrac%7BQ%7D%7BA%7D%20%20%3D%20%20-%5Cepsilon%20_o%20E)
![\eta = -\epsilon _o E](https://tex.z-dn.net/?f=%5Ceta%20%20%3D%20%20-%5Cepsilon%20_o%20E)
Where
is the charge density
The ball can't reach the speed of 20 m/s in two seconds, unless you THROW it down from the window with a little bit of initial speed. If you just drop it, then the highest speed it can have after two seconds is 19.6 m/s .
If an object starts from rest and its speed after 2 seconds is 20 m/s, then its acceleration is 20/2 = 10 m/s^2 .
(Gravity on Earth is only 9.8 m/s^2.)
Answer: the correct option is B ( on the half of the road that the vehicle is traveling).
Explanation: according to Georgia Code About Pedestrians; The driver must stop and remain stopped to let a pedestrian cross at a crosswalk when the pedestrian is
on the half of the road that the vehicle is traveling.
Of the materials listed wood is the best insulator. It would be the least hot if exposed to similar temperatures.