physics please help

One end of a thin rod is attached to a pivot, about which it can rotate without friction. Air resistance is absent. The rod has a length of 0.59 m and is uniform. It is hanging vertically straight downward. The end of the rod nearest the floor is given a linear speed v0, so that the rod begins to rotate upward about the pivot. What must be the value of v0, such that the rod comes to a momentary halt in a straight-up orientation, exactly opposite to its initial orientation?

  1. 👍
  2. 👎
  3. 👁
  1. The initial kinetic energy of the bar, which is
    (1/2) I wo^2 = (1/2)*M (L^2/3)*(vo/L)^2
    = (1/6)*M vo^2

    Must equal the increase in potential energy in the upside-down position, which is
    M g L
    since the center of mass raises by an amount L.

    I is the moment of inertia of the rod about the pivot at the top.

    M cancels out and you are left with
    (1/6)vo^2 = g*L

    Solve for vo

    1. 👍
    2. 👎
  2. a uniform rod of strenght b stands vertically uoright on a rough floor and tge tips over what is the rod's angular velocity when it hits the floor

    1. 👍
    2. 👎

Respond to this Question

First Name

Your Response

Similar Questions

  1. physics class-Help!!!

    A 3.0 m rod is pivoted about its left end.A force of 6.0 N is applied perpendicular to the rod at a distance of 1.2 m from the pivot causing a ccw torque, and a force of 5.2 is applied at the end of the rod 3.0 m from the pivot.

  2. physics

    The figure shows an overhead view of a 3.00-kg plastic rod of length 1.20 m on a table. One end of the rod is attached to the table, and the rod is free to pivot about this point without friction. A disk of mass 37.0 g slides

  3. Physics

    A nonuniform 2.0-kg rod is 2.0 m long. The rod is mounted to rotate freely about a horizontal axis perpendicular to the rod that passes through one end of the rod. The moment of inertia of the rod about this axis is 4.0 kg m2. The

  4. Physics

    A long thin rod of mass M = 2:00 kg and length L = 75:0 cm is free to rotate about its center as shown. Two identical masses (each of mass m = .403 kg) slide without friction along the rod. The two masses begin at the rod's point

  1. physics

    A thin rod has a length of 0.25 m and rotates in a circle on a frictionless tabletop. The axis is perpendicular to the length of the rod at one of its ends. The rod has an angular velocity of 0.33 rad/s and a moment of inertia of

  2. Physics

    A uniform rod of mass M and length d is initially at rest on a horizontal and frictionless table contained in the xy plane, the plane of the screen. The figure is a top view, gravity points into the screen. The rod is free to

  3. science-physics

    A worker sits at one end of a 183-N uniform rod that is 2.80 m long. A weight of 107 N is placed at the other end of the rod. The rod is balanced when the pivot is 0.670 m from the worker. Calculate the weight of the worker

  4. physics

    Two blocks, each of mass m, are attached to the ends of a massless rod which pivots as shown in Figure 8-40. Initially the rod is held in the horizontal position and then released. Calculate the magnitude and direction of the net

  1. AP Physics

    A uniform thin rod of length 0.3m and mass 3.5kg can rotate in a horizontal plane about a vertical axis through its center. The rod is at rest when a 3g bullet traveling in the horizontal plane of the rod is fired into one end of

  2. Physics

    A rod is lying on the top of a table. One end of the rod is hinged to the table so that the rod can rotate freely on the tabletop. Two forces, both parallel to the tabletop, act on the rod at the same place. One force is directed

  3. Physics

    A force of 60 N is exerted on one end of a 1.0-m-long lever. The other end of the lever is attached to a rotating rod that is perpendicular to the lever. By pushing down on the end of the lever, you can rotate the rod. If the

  4. Physics

    A mass of 100g is attached to one end of a massless rod, 10cm in length, which is pivoted about the opposite end. The rod is held vertical, with the mass at the top, and released. The rod swings. A. What is the speed of the mass

You can view more similar questions or ask a new question.