Recent content by Barkeeper Moe

  1. B

    How Does Friction Affect Work in a Pulley System with Unequal Masses?

    A mass of 1kg rests on a horizontal table. It is connected by a taut, light, inextensible string passing over a smooth fixed pulley, at the edge of the table, to another mass of 3kg hanging vertically. The 3kg mass it at a height of 0.5 metres above an inelastic floor when the system is released...
  2. B

    Calculation Error: Iodine-131 Half-Life & 30 Days

    No of HLs = 3.7313432835820895522388059701493 No of HLs Activity % 0 131 100 1 65.5 50 2 32.75 25 3 16.375 12.5 4 8.1875 6.25 So its somewhere between 12.5% and 6.25%... Cant quite remember how to do it exactly. My guess would be from 3...
  3. B

    Calculating Work and Power in Mechanical Systems

    KE = 1/2mv^2 PE = mgh Work done = change in energy = force x displacement Power = rate of doing work = force x velocity F = ma It has something to do with the above formulae, but no matter how i use them I can't get the right answer.
  4. B

    Calculating Work and Power in Mechanical Systems

    I forgot to say, these are the answers: 1. 238.2 W 2. 3.8625 J I've just no idea how to get them :-(
  5. B

    Calculating Work and Power in Mechanical Systems

    1. Find the power required to raise water 3m vertically from a tank and discharge it through a nozzle of cross-sectional area 0.0003m^2 at a speed of 10m/s. 2. A mass of 1kg rests on a horizontal table. It is connected by a taut, light, inextensible string passing over a smooth fixed pulley...
Back
Top