A flywheel, that has most of its mass at its rim, can rotate about an axis that is perpendicular to the wheel at its center. Rotating flywheel provide a means for storing energy in the form of rotational kinetic energy, and are being used in some electric power plant to store excess electrical energy. How fast would a M= 14-kg flywheel with radius R = 0.35 m, have to rotate (that is, what should be its in rad/s), to store . × of rotational kinetic energy? (Rotational Inertia of a flywheel is I = MR2

200000000

Explanation:

just did the test

a

explanation:

no diagram was provided, but i'm guessing it's the one i've attached to my answer.

here, a mechanical force turns the rod.   this generates an electric current in the coil, which powers the bulb.

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.