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Homework Help: Physics question tension!

  1. Nov 1, 2011 #1
    1. The problem statement, all variables and given/known data

    A 2.0 X 10^-4 kg spider is suspended from a thin strand of spider web. The greatest tension the strand can withstand is 2.0 X 10^-3 N. if the spider was to ascend the strand from rest going to 1.0 m/s in 4.0 s with a steady acceleration, will the strand be able to support the motion?

    2. Relevant equations

    3. The attempt at a solution

    2.0 X 10^-4 kg (9.8 m/s²) = 1.96 X 10^-3 kg(m)/s²

    2.0 X 10^-4 kg (0.25 m/s²) = 5.0 X 10^-5

    1.96 X 10^-3 + 5.0 X 10^-5 = 2.46 X 10^-4
    yes because 2.0 X 10^-3 is greater than 2.46 X 10^-4
  2. jcsd
  3. Nov 2, 2011 #2


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    Homework Helper

    Something has gone wrong here. Better run it through again.
    It looks like your approach is correct, though difficult to follow.
    Maybe better to write
    F = ma
    T - mg = ma
    T = ma + mg = m(a+g), then put in the numbers.
    This way, there is only one calc, half the chance of killing it with a typo!
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