I attached the full question.
We know that for a parallel-plate capacitor the surface charge density is given by the following formula:

Where V is the voltage between the plates and d is separation.
Voltage is by definition:

Voltage is analog to the mechanical work done by the force.
Above formula is correct only If the field is constant, and we can assume that it is since no function has been given.
The charge density would then be:

Please note that elecric permittivity of air is very close to elecric permittivity of vacum, it is common to use them <span>interchangeably</span>.
Answer:
101.54m/h
Explanation:
Given that the buses are 5mi apart, and that they are both driving at the same speed of 55m/h, rate of change of distance can be determined using differentiation as;
Let l be the be the distance further away at which they will meet from the current points;
#The speed toward each other.

Hence, the rate at which the distance between the buses is changing when they are 13mi apart is 101.54m/h
Answer:
Density is the mass to volume ratio of an object.
> It tells you how compact the mass is.
> Density = mass/volume
The density of water is 1 g/ml or 1 kg/L or 1000 kg/m3
• If an object has a density less than that of water, it
will float.
• If an object has a density more than that of water, it
will sink
Explanation:
hope this helps some
Answer:
it must be helical motion in which the charge particle will move uniformly along z axis and simultaneously it will move in circular path in xy plane.
Explanation:
Magnetic field is along z axis while velocity is in x-z plane
so we will have

so here we can say

so we will have

so here the net force on the charge is perpendicular to its x directional velocity along - Y direction
So due to this component of motion it will move along a circle while other component of the motion will remain uniform always
So here it is combination of two parts
1) Uniform circular motion
2) Uniform motion
So we can say that it must be helical motion in which the charge particle will move uniformly along z axis and simultaneously it will move in circular path in xy plane.