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Homework Help: Physics Problems !

  1. Jan 11, 2010 #1
    1. A bucket of mass 4.03 kg is pulled by a rope and accelerated straight upwards at a rate of 1.62 m/s2. What is the tension in the rope? Express your answer in Newtons.

    2. Two masses are connected by a light string and pulley as shown below. The mass on the left is 2.34 kg and the mass on the right is 3.60 kg. The system is released from rest. If the heavier mass starts at a height of 1.51 m above the ground, at what time will it strike the ground? Express your answer in seconds.

    3. A boy purchases a copy of the Mona Lisa and hangs it from two ropes as shown below. The angle, is 27.8 degrees. If the Mona Lisa's mass (including the frame) is 4.56 kg, what is the tension in each rope? Express your answer in Newtons.

    ~For the first one I got 46.02260000000001 Newtons... but I don't know. =/
  2. jcsd
  3. Jan 11, 2010 #2
    I know they're most likely 'easy,' but I am really bad at this. I'm just really looking for someone to guide me through them I guess.
  4. Jan 11, 2010 #3


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    Hi, Alpha2, welcome to PF, your first answer is correct (but get rid of all those extra numbers after the decimal point!), so you're doing something right :smile:, but please show your relevant equations and attempt at a solution for the next two, per forum rules , following the format listed when you post. Also, please post each question separately, showing what equations you think apply and how you might solve the problem. Also, a picture or sketch would help. Thanks.
  5. Jan 11, 2010 #4
    For the second one, treat these types of problems as differences in masses. So having a 3kg mass on one side, and having a 2kg mass on the other side, is exactly the same as having a 1kg mass(3-2) on one side and nothing on the other.

    So all you have to do is use your formula for classical mechanics which is d = x + vt + (at^2)/2. since your initial velocity and initial distance are both 0, you are going to have 1.51 x 2 = at^2. Once you find a, which shouldn't be hard, just solve for t.
  6. Jan 11, 2010 #5
    and by distance i mean initial distance which i denoted using 'x'.
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