course phy121
If the velocity of the object changes from 3 cm / sec to 14 cm / sec in 7 seconds, then at what average rate is the velocity changing?Average rate of velocity change is 1.57cm/sec/sec
A cart rolling from rest down a constant incline of length 76 cm requires 7.8 seconds to travel length of the incline.
What is its average velocity?
9.74cm/sec
An object which accelerates uniformly from rest will attain a final velocity which is double its average velocity.
What therefore is the final velocity of this cart?
19.48cm/sec
What average rate is the velocity of the cart therefore changing?
2.5cm/sec/sec
At what average rate does the velocity of an automobile change, if it accelerates uniformly down a track, starting from rest, and if it requires 11 seconds to cover a distance of 110 meters.
*change*
vAve was 10m/s. So with a starting point (vI) of 0m/s and an unknown vF, you can plug it into the averaging equasion.
x=vF
(0 + x)/2=10
(0 + x) = 10 * 2
0 + x = 20
x = 20 - 0
vF = 20m/s
Divide vF by 11 seconds and it gives you a rate of increase of ~1.818m/s/s
Verified by multiplying the half way point of 5.5sec to give you the vAve.
1.818 * 5.5 = 9.999m/s = ~10m/s
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