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Gooner5
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Three blocks, each of mass 13 kg are on a frictionless table. A hand pushes on the left most box (A) such that the three boxes accelerate in the positive horizontal direction as shown at a rate of a = 1.4 m/s2.
1)What is the magnitude of the force on block A from the hand?
2)What is the net horizontal force on block B?
For number 1 I was able to get the answer by adding up all the blocks and multiplying that by the acceleration but I am confused by why this is right. Before I did this I thought that the answer would be the mass of A * 1.4. Why does the force by the hand on block A include the other blocks as well? Is it because the whole system is accelerating and for that to happen the force has to take into account the other blocks as well?
For number 2 I found the force done on the system to be (13+13+13)*1.4 = 54.6N. I then found that the force that object C does on block B and the force that object A does on block B would 13*1.4= 18.2N. I then added the force done on the system by the hand with block A and subtracted that by the force by C on B to get 54.6, but this is not the right answer. What should I be looking for in this problem?
Thanks
1)What is the magnitude of the force on block A from the hand?
2)What is the net horizontal force on block B?
For number 1 I was able to get the answer by adding up all the blocks and multiplying that by the acceleration but I am confused by why this is right. Before I did this I thought that the answer would be the mass of A * 1.4. Why does the force by the hand on block A include the other blocks as well? Is it because the whole system is accelerating and for that to happen the force has to take into account the other blocks as well?
For number 2 I found the force done on the system to be (13+13+13)*1.4 = 54.6N. I then found that the force that object C does on block B and the force that object A does on block B would 13*1.4= 18.2N. I then added the force done on the system by the hand with block A and subtracted that by the force by C on B to get 54.6, but this is not the right answer. What should I be looking for in this problem?
Thanks