#$&*
course phy 201
Problem Number 3An object is given a velocity of 14 cm/s up a ramp on which its acceleration is known to have magnitude 6 cm/s^2.
• At what later times does it pass a point 5 cm up the ramp from its initial position?
• What is its maximum distance up the ramp from its initial point?
initial - 0
final 14cm/s
(14 + 0 )/ 2 = 7cm/s
@& You are given the displacement, acceleration and initial velocity. These three quantities determine all other quantities on that interval, so you cannot assume a value for any other quantity. You appear to have assumed a final velocity of zero; however this is not consistent with the values of the three given quantities.*@
@& OK, I just realized that you are solving for the maximum displacement. The first question remains to be answered (I was reading your solution as if it was for the first question).
You've done a pretty good job with the second question. However note that the given 14 cm/s is the initial velocity, not the final velocity. At maximum displacement the velocity does reach zero, so the final velocity would be zero.
Now your calculation vAve = (14 cm/s + 0) / 2 = 7 cm/s makes sense, as does the rest of your solution. *@
5cm/7cm/s = .714 seconds
14 cm/s / 6 cm/s^2= 2.3333 seconds
2.3333 x 14 cm/s = 32 cm
@& Bottom line, you've done pretty well here. Check my notes, but don't let them confuse you.*@