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Conceptual problem about two blocks released from a compressed string

  1. Nov 15, 2007 #1
    1. The problem statement, all variables and given/known data

    Two blocks, A and B, are connected by a compressed string. The mass of bock A is twice that of block B. Immediately after release, compare the net force on block A to the net force on block B. The table is frictionless and the mass of the spring is zero.

    1)There is no net force on block A or block B.

    2)Fnet of A is equal in magnitude and direction to Fnet B and not zero.

    3) Fnet B, will be in the opposite direction and half as large as Fnet A.

    4)Fnet A, and Fnet A are both directed toward the left with Fnet A larger than Fnet A, but not twice as large. Block A is pulling block B.

    5) Fnet A, will be in the opposite direction and half as large as Fnet B.

    6) Fnet A is equal in magnitude and opposite in direction to Fnet B, and not zero.

    2. Relevant equations

    I don't think you need any equations.

    3. The attempt at a solution

    I think it is 5 because A is twice as massive as B so it would take more force to move it the the same and they will be going in opposite directions. Do you agree?
  2. jcsd
  3. Nov 15, 2007 #2
    I change my mine I think its 6.
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