phy201
Your 'cq_1_06.1' report has been received. Scroll down through the document to see any comments I might have inserted, and my final comment at the end.
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6.1
For each situation state which of the five quantities v0, vf, `ds, `dt and a are given, and give the value of each.
A ball accelerates uniformly from 10 cm/s to 20 cm/s while traveling 45 cm.
answer/question/discussion: ->->->->->->->->->->->-> :
v0= 10 cm/s
vf= 20cm/s
ds= 45 cm
'dt= 'ds/vave
'dt = 45cm/15cm/s
'dt=3s
a= 'dv/'dt
a= 10cm/s /3s
a= 3.3cm/s^2
#$&*
A ball accelerates uniformly at 10 cm/s^2 for 3 seconds, and at the end of this interval is moving at 50 cm/s.
answer/question/discussion: ->->->->->->->->->->->-> :
a=10cm/s^2
'dt= 3 seconds
Vf= 50cm/s
Vf= V0 + a * dt
50cm/s= V0 + 10cm/s^2 * 3s
50cm/s = v0 + 30cm/s
V0= 20 cm/s
ds=(vf+v0)/2 * 'dt
ds= (50cm/s-20cm/s) /2 * 3s
ds= 15 cm/s *3s
ds= 45cm
#$&*
A ball travels 30 cm along an incline, starting from rest, while accelerating at 20 cm/s^2.
answer/question/discussion: ->->->->->->->->->->->-> :
'ds=30cm
v0=0
a= 20cm/s^2
vf^2 = V0^2 +2a'ds
Vf^2 = 0 + 2(20cm/s^2) 30cm
Vf^2 = 0 + 40cm/s^2 * 30 cm
Vf^2 =1200cm^2/s^2
Square root Vf= square root 1200cm^2/s^2
Vf= 35 cm/s
You should also consider vf = - sqrt( 1200 cm^2 / s^2). The negative solution doesn't make sense for this particular problems, but on many problems both the positive and negative solutions, and sometimes just the negative solution, make sense . You'll be seeing example of this in the future.
'ds= vave *dt
30cm = 17.5cm/s * 'dt
'dt= 1.71s
#$&*
Then for each situation answer the following:
Is it possible from this information to directly determine vAve?
answer/question/discussion: ->->->->->->->->->->->-> :
Yes you can determine vave from the information given, but you had to take the proper steps using the information at hand to find vave. So if you are only given the information for vf then you had to find
v0 before you could find vave.
#$&*
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about 1 hour
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Excellent work. See my one note.