Closed 5 years ago.
You are watching: How do you find the change in velocity
"A runner runs at 4 m/s on a circular monitor constantly. A and also B space opposite clues on the track, therefore A is the beginning point and also B is halfway about the track. Calculation his adjust in velocity indigenous A come B, if any."
I recognize that velocity is a vector, and also therefore has a direction. Logically his adjust to me is -8 m/s. As -4 - 4 = -8, however is the adjust 8 or -8? Or is the 0 because 4 - 4 = 0?
Help is appreciated.
If you specify your axes in such a method that the runner has actually a rate of 4m/s in the y direction in allude A, the the velocity in point A is:
$V_A = 4 , extm/s , haty + 0 , extm/s , hatx$
Your runner must have a rate of -4m/s in the y direction in point B, you gain the velocity:
$V_B = -4 , extm/s , haty + 0 , extm/s , hatx$
The speed in the x direction is unchanged.
Regardless of an option of axis the equation need to be: $V_A + change = V_B = -V_A$, therefore the adjust in this situation must constantly be equal to $-2 cdot V_A$
You initial guess: v of -8m/s, v regard to the magnitude of the velocity change, is correct if you location your early vector together with one of the axes of her coordinate mechanism of choice.
enhance this prize
edited Nov 15 "15 in ~ 16:44
answered Nov 15 "15 at 16:36
A. NielsenA. Nielsen
1611 bronze argorial
add a comment |
Change that velocity is definitely -8m/s, follow to vector summation.Magnitude of change of velocity is 8m/s. "-" sign suggests that the change is taking in the various other direction,i.e. In the direction opposite to the initial direction. 4-4=0 is the readjust in speed , no velocity
enhance this answer
answer Nov 15 "15 at 16:37
Syed JaffriSyed Jaffri
6177 bronze title
add a comment |
Not the prize you're spring for? Browse other questions tagged homework-and-exercises kinematics velocity vectors or questioning your very own question.
Featured top top Meta
detect normal and also tangential velocity and also acceleration for motion along a 3D curve
how to technique this circular movement question?
classic mechanics trouble - loved one velocity
have the right to I uncover out magnitude and also direction (+starting point) that a vectror using only one method? (graphical or mathematical)
exactly how to discover the angular velocity vector offered the velocity, radius and acceleration vectors?
hot Network questions more hot concerns
ridge Exchange Network
site design / logo © 2021 stack Exchange Inc; user contributions licensed under cc by-sa. Rev2021.11.5.40661
See more: What Evolves From A Shiny Stone, Pokémon: Every Evolution Stone Evolution