Basic Q's Net Force and Acceleration

AI Thread Summary
The discussion centers on the accuracy of answers provided in a teacher's guide regarding net forces and accelerations in a physics homework assignment. For question #2, the participant calculates net forces and finds that D has the greatest force, while A, B, and C are equal. The calculated accelerations also show that A and C have the highest values, followed by B and D, which raises questions about the teacher's guide's clarity. In question #3, the participant computes various accelerations and ranks them, agreeing with their own findings. Overall, the conversation highlights discrepancies between student calculations and the teacher's guide answers.
kstbts
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Homework Statement


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Homework Equations


I am wondering if the answers given in the teacher's guide are incorrect.
Ans given for #2: [All same], [A,C,B,D]
Ans given for #3: [A,C,D,B]

The Attempt at a Solution


My answers:
#2a: Net forces: A,B,C are 5N; D is 10N. Therefore the order of the net forces from greatest to least is D, followed by A,B,C which are equal.
#2b: Their accelerations are a) 5N/5kg=1m/s2 b) 5N/10kg=0.5m/s2 c) 5N/5kg=1m/s2 d) 10N/20kg=0.5m/s2. Therefore the order of their accelerations from greatest to least would be A&C, which are the same, followed by B&D which are the same. Admittedly, the teacher's guide could be saying the same thing for this second part of the answer, but I can't be certain since their answer says nothing about A=C and B=D.
#3: Accelerations are:
a) a=(1000N-800N)/(1000N/9.8)=1.96m/s2
b) a=1.23 m/s2
c) a=1.4 m/s2
d) a= 0.98 m/s2
Therefore the order from greatest to least is A,C,B,D
 
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Hi kstbts. http://img96.imageshack.us/img96/5725/red5e5etimes5e5e45e5e25.gif

I like your answers, they are the same as mine.
 
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Thanks NascentOxygen.
 
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