Abird is flying to the right when a gust of wind causes the bird to accelerate...
A bird is flying to the right when a gust of wind causes the bird to accelerate leftward at 0.5 m/s^2 for 3 s. After the wind stops, the bird is flying to the right with a velocity of 2.5 m/s.
Assuming the acceleration from the wind is constant, what was the initial velocity of the bird before the gust of wind?
Let say Initial Velocity of Bird = U m/s
Final Velocity of Bird V = 2.5 m/s
acceleration a = -0.5 m/s² ( as opposite to the fly direction)
Time T= 3 sec
V = U + aT
=> 2.5 = U + (-0.5)3
=> 2.5 = U -1.5
=> U = 4 m/s
the initial velocity of the bird before the gust of wind = 4 m/s
physics means: "the branch of science concerned with the nature and properties of matter and energy. the subject matter of physics, distinguished from that of chemistry and biology, includes mechanics, heat, light and other radiation, sound, electricity, magnetism, and the structure of atoms."
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.