Tuesday, November 22, 2011

How to draw a velocity vector for these three situations?

A marble is positioned at the top of a ramp and the ramp is placed on a table top. Draw a velocity vector for when


1) the ball just rolls off the table top


2) in mid flight


3) just before it hits the ground





please help me, my teacher isn't a good one and i have no idea what to do.|||1. Just before the ball rolls off the table top it is going horizontally.


2. In mid-flight it is going both horizontally and vertically downward.


3. Just before hitting the ground it is still going horizontal and vertically downward but this time the vertical component is bigger than before.|||It is pretty much how jcm said (unless we are building a wrong mental image, ofc).





I think this page is a good one to understand how the movement works (and therefore how the velocity vector behaves): http://www.physicsclassroom.com/class/1d鈥?/a>








Basically all you need to do is look at a given instant (the ball leaving the table, for example) and imagine: If there was no gravity, no friction or any other force, in what direction would the marble continue its movement after this instant? It will be a straight line and the vector follows it (you will just not have a precise size, but the overall direction you get).

No comments:

Post a Comment