Recent content by Galileo's Ghost

  1. G

    Finding the de Broglie wavelength from momentum

    The unit MeV/c is actually a unit of momentum...no need to divide by the speed of light, it is already factored in through the use of this unit notation. Generically, energy units consist of the quantities (mass)(length)2 / (time)2. If you were to divide energy by speed, you would be left...
  2. G

    How Do You Calculate the Maximum Speed in a Frictionless Pulley System?

    You may want to reconsider your energy analysis at the start. You claim a PE = 0, but consider that the 1 kg mass will be falling. If it will fall, then it will experience a change in PE. Also consider that the 1 kg mass can only fall a distance equal to how far the spring is stretched. So...
  3. G

    What is the tension on a high wire supporting an acrobat at a 5 degree angle?

    55kg = mass NOT tension. Your question asks you to solve for tension...that should remain as your unknown variable in the equation.Regarding the sin/cos issue. The trig function comes about from an understanding of right triangle trigonometry. Whether to use sin or cos really depends upon...
  4. G

    What is the tension on a high wire supporting an acrobat at a 5 degree angle?

    There really is no Normal force here. The upwards support is coming from the vertical components of the tension in the wire. If you eliminate the Fn in your equation, you should be good.
  5. G

    What is the tension on a high wire supporting an acrobat at a 5 degree angle?

    The horizontal components will "cancel each other out". The 2 vertical components of tension, however, do not cancel each other as they are both upwards. So, write an expression that sums up all the forces vertically and remember that all together they must result in ZERO acceleration.
  6. G

    What is the tension on a high wire supporting an acrobat at a 5 degree angle?

    Tension in a wire is the same throughout the wire. The tension is acting along the length of the rope which is described as 5 degrees from the horizontal. Thus, a component of this tension is horizontal and a component is vertical...so yes, resolve the tension vectors into components.
  7. G

    What is the tension on a high wire supporting an acrobat at a 5 degree angle?

    Remember that the acrobat in question is merely standing in the middle. There is no acceleration in the vertical or horizontal directions...ie equilibrium. Have you tried drawing a free body diagram yet? Identify all the forces and consider how those relate to each other for a condition of...
  8. G

    What is the Speed of Sound from Resonance?

    So, this seems to boil down to that 65 cm corresponding to 1/2 wavelength in the long tube situation...but I do not understand why this is so...
  9. G

    What is the Speed of Sound from Resonance?

    Homework Statement One end of a plastic tube, open at both ends, is placed into a large container of water. A 256 Hz tuning fork, continuously vibrating, is held over the end of the tube in the air and the tube is raised until maximum loudness is observed. The plastic tube is then raised...
  10. G

    Momentum in Collisions: Solving for Velocity and Kinetic Energy Conversion

    Remember that velocity, and hence momentum, are vector quantities and need to be treated as such when adding them together. I think you attempted to do this with the minus sign, but these vectors are not opposite in direction. They are at 90 degrees to one another. Draw a diagram of the...
  11. G

    What causes constand acceleration?

    If the risk piece was moving the same displacement each picture frame, then it would not be experiencing accelerated motion. It would be moving with constant velocity. Anyway, as far as the cause of acceleration, look up Newton's Laws of motion and read them.
  12. G

    A rock is thrown off of a cliff

    You have studied the kinematic equations, haven't you? Your solution will require these.
  13. G

    Rocket Acceleration: Kinematics Problem Solved

    Acceleration is 9.80 m/s^2 downward for objects that are in free fall. The rocket is not in free fall. It is burning fuel to generate a thrust accelerating the rocket upwards. The bolt IS in free fall over the last 6 seconds. During the first 4 seconds, however, the bolt was experiencing the...
  14. G

    Finding centripetal acceleration

    v = 0.38pi/.28 ...and this is the linear velovity, r(theta)/t, not the acceleration. Here is where you are making an error... you did not square the theta or the t
  15. G

    Rocket Acceleration: Kinematics Problem Solved

    Keep in mind the delta y for the rocket in the first 4 seconds will have the same magnitude but opposite direction as the delta y for the bolt in the final 6 seconds. So (delta y)rocket = -(delta y)bolt. Also the vf for the rocket (and consequently the vi of the bolt) can be solved in terms of...
Back
Top