A 1000 lb boulder B is resting on a 500 lb platform A when truck C accidentally accelerates to the right (truck in reverse). Which of the following statements are true? (select two answers). a) The tension in the chord is 1500 lbs
b) The tension in the chord is greater than 1500 lbs
c) The tension in the chord is less than 1500 lbs
d) The normal force between A and B is larger than 1000 lbs
e) The normal force between A and B is less than 1000 lbs
f) The normal force between A and B is equal to 1000 lbs

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.

its lower due to the doppler effect.: apex