A2.0-cm-diameter parallel-plate capacitor with a spacing of 0.50 mm is charged to 200 v? what is the total energy stores in the electic field? u= jwhat is the energy densityu=/m^3

1)

The capacitance of a parallel-plate capacitor is given by:

where

is the vacuum permittivity

A is the area of each plate

d is the distance between the plates

Here, the radius of each plate is

so the area is

While the separation between the plates is

So the capacitance is

And now we can find the energy stored,which is given by:

2) 0.71 J/m^3

The magnitude of the electric field is given by

and the energy density of the electric field is given by

and using

, we find

russian is not my first language, so i'm afraid i can't write out an answer in russian, but hopefully you can find a way to do so. here's my best translation of the problem: you're given a plot of a particle's position in one-dimensional space over time, and you're asked to find either the total distance traveled by the particle after 6 seconds had elapsed, or the total displacement of the particle after 6 seconds.

if you want the total distance traveled, you would first need to determine the particle's velocity as a function of time, then integrate that over the 6-second interval. we know the position function is quadratic with roots at 0 and 6, so we have

where is unknown. because the position is parabolic, there is symmetry about the midpoint at , and we know that

so that the position function is

which means the velocity is

then the total distance traveled is

so the total distance traveled is 20 m.

on the other hand, if you want to find displacement: the particle starts at and ends at , so its displacement is 0.