**Problem regarding Acceleration**
1. An object has a constant acceleration of 8m/s/s. How far will the object reach after 5 seconds?
Given:
a=8 m/s^2
t= 5 s
d=?
Most of the class solution:
They first derived final velocity. The formula for a is a= (vf-vi)/(tf-ti)
8m/s/s=(vf-vi)/5
vf=40m/s
they derived distance by multiplying velocity and time. Therefore:
d=(40m/s)(5s)
d=200m
My solution:
Through advanced reading, I managed to learn a formula d=1/2(at^2)
d=1/2[(8 m/s/s)(5^2)]
d=1/2[(8m/s/s)(25)]
d=1/2(200)
d=100m
Which one is correct? My solution or my class' solution?
2. A body has a constant acceleration of 6m/s/s and traveled 50m. What is its velocity?
Given:
a=6 m/s^2
d=50 m
v=?
t=?
d=(v^2)/2a
50=(v^2)/2(6)
50=v^2/12
600=v^2
v=24.49489743 m/s
t=2.041241452 s
Is my solution correct or does it need some work?
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Last edited by RPSGCC733; Aug 22nd 2012 at 05:29 AM.
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