Phy 201
Your 'cq_1_12.1' 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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Masses of 5 kg and 6 kg are suspended from opposite sides of a light frictionless pulley and are released.
• What will be the net force on the 2-mass system and what will be the magnitude and direction of its acceleration?
answer/question/discussion: ->->->->->->->->->->->-> :
Side A:
F = m * a
F = 6 kg (9.8 m/s/s)
F = 58.8 Newtons
Side B:
F = m * a
F = 5 kg (9.8 m/s/s)
F = 49 Newtons
Fnet = 58.8 Newtons – 49 Newtons = 9.8 Newtons towards the 6kg side
#$&*
• If you give the system a push so that at the instant of release the 5 kg object is descending at 1.8 meters / second, what will be the speed and direction of motion of the 5 kg mass 1 second later?
answer/question/discussion: ->->->->->->->->->->->-> :
Side A:
vf = v0 + a (`dt)
vf = 0 m/s + 9.8 m/s/s(1s)
vf = 9.8 m/s
Side B:
vf = v0 + a (`dt)
vf = 1.8 m/s + 9.8 m/s/s(1s)
vf = 11.6 m/s
11.6 m/s – 9.8 m/s = 1.8 m/s, with the 5kg mass moving down
Both sides accelerate at the same rate, and the system as a whole has a single velocity at every instant.
See the link provided below.
#$&*
• During the first second, are the velocity and acceleration of the system in the same direction or in opposite directions, and does the system slow down or speed up?
answer/question/discussion: ->->->->->->->->->->->-> :
During the first second, the velocity is moving towards the 5kg mass and the acceleration is moving toward the 6kg mass. The system will slow down as the initial velocity wears off.
#$&*
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20 minutes
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Please compare your solutions with the expanded discussion at the link
Solution
Self-critique your solutions, if this is necessary, according to the usual criteria. Insert any revisions, questions, etc. into a copy of this posted document. Mark any insertions with &&&& so they can be easily identified.