#$&*
course Phy 121
9/18 10pm
Physics I Assignment 07: Move the dot straight from the left of the screen to the right, taking a few seconds to complete the motion. Which vector represents the velocity, and which represents the acceleration? When is the acceleration vector longest? When is the velocity vector longest? When do the vectors have the same direction, and when are their directions opposite?
******
The green vector represents the veloctiy and the blue vector represents the acceleration. The velocity vector is the longest If you slide your finger quickly. The acceleration vector is longest either just as you are starting to slide your finger quickly or (in the opposite direction) right when you stop moving after a quick slide. The vectors have the same direction as you are moving along left to right and you are picking up speed. The vectors have opposite directions when you slow down. The velocity vector gets smaller, but it still points to the right, but the acceleration vector shoots out to the left.
*****
Repeat but move the dot as quickly as possible from left to right. Describe the behaviors of the two vectors.
******
The acceleration vector shoots out rapidly and long to the right followed by a growing long velocity vector. As you approach the right hand side and slow down the velocity vector shortens and the acceleration vector shoots out to the left with a long vector that quickly shrinks again.
*******
Now start in the upper left-hand corner, moving at first to the right, but as you continue to move to the right gradually begin arcing downwards so that you follow a graceful (?) curve from upper right to lower left. Describe the behavior of the velocity and acceleration vectors.
******
Because I did this exercise on a laptop with a mousepad, I could not make a single smooth sweep like I could presumably do with an external mouse and a lot of desk space. I did see something interesting. Because I had to go in about 4 or 5 legs in the journey, but I was still trying to be smooth the vectors almost seemed like the arms of a swimming creature, as I started acceleration would stretch out followed by velocity, but as I ran out of mousepad space, the velocity arm would retract and the acceleration arm would emerge in the opposite direction as the swimming creature came to a temporary stop before starting the process again.
@&
Very neat observation. I swam 2000 yards awhile ago so it's especially striking.
*@
*******
Now move the dot around a circular path. Follow a slow circular path, then try to double your speed along the same path. How does the direction of the acceleration vector compare with that of the velocity vector? If you double the speed, then what happens to the magnitudes of the velocity vector and the acceleration vector?
*****
The two vectors are nearly perpendicular to each other when going in a circle. I don't know if I was able to exactly double the speed, but certainly as I did, the vectors increased in size. Briefly at first the acceleration vector would be larger, to soon be overtaken by a larger velocity vector.
*******
Submit a copy of your results and insights using the Submit Work Form, with title 'Ladybug Motion'."
@&
Excellent observations.
*@