#$&*
course Phy 121
The problem:A ball accelerates at 8 cm/s^2 for 3 seconds, starting with velocity 12 cm/s.
What will be its velocity after the 3 seconds has elapsed?
answer/question/discussion:
(12cm/s)+(3s*8cm/s^2)= 288cm/s
@&
(12cm/s)+(3s*8cm/s^2) is correct, but
(12cm/s)+(3s*8cm/s^2) = 12 cm/s + 24 cm/s = 36 cm/s.
It appears that you multiplied when you should have added.
*@
#$&*
Assuming that acceleration is constant, what will be its average velocity during this interval?
answer/question/discussion:
(288cm/s+12cm/s)/2=150cm/s
#$&*
How far will it travel during this interval?
answer/question/discussion:
150cm/s * 3s = 450cm
#$&*
@&
Your first answer is incorrect.
Your last two follow correctly if you assume your answer for the first.
Simple error. Check my note.
*@