Read the following paragraph from the introduction [paragraphs 1-4]. Energy cannot be created or destroyed, meaning that the total amount of energy in the universe has always been and will always be constant. However, this does not mean energy is unchangeable. It can change form and even transfer between objects. Which answer choice BEST supports the idea that energy remains constant during an energy transformation? (A) They move faster and spread out, creating a lower density of molecules, or quantity of molecules in that volume, at the bottom of the pot. (B) The process repeats, creating a current of molecules sinking, heating up, rising, cooling down and sinking again. (C) The ball continues losing potential energy and gaining kinetic energy until it reaches the bottom of the hill. (D) On Earth, however, the ball stops at the bottom of the hill due to the kinetic energy being transformed into heat by the opposing force of friction.

the answer is a 3.8cm

explanation:

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.