An ideal spring of negligible mass is 11.00 cm long when nothing is attached to it. When you hang a 3.10-kg weight from it, you measure its length to be 12.40 cm . Part A If you wanted to store 10.0 J of potential energy in this spring, what would be its total length

Total length is 15.7 centimeters.

Explanation:

The potential energy is modelled by applying Principle of Energy Conservation and Work-Energy Theorem:

The spring constant can be found by using Statics:

Where .

The total length is isolated from energy expression:

what is the actual question though?

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.