PHYSICS 1 ..'''''''''''''''''''''''' helllpppppppp

A girl of mass (Mg) is standing on a plank of mass (Mp). Both are originally at rest on a frozen lake that constitutes a frictionless, flat surface. The girl begins to walk along the plank at a constant velocity (vgp) to the right relative to the plank. (The subscript gp denotes the girl relative to plank. Use any variable or symbol stated above as necessary.)

(a) What is the velocity vpi of the plank relative to the surface of the ice?

(b) What is the girl's velocity vgi relative to the ice surface?

  1. 👍 0
  2. 👎 0
  3. 👁 2,426
  1. The total momentum remains zero and the center of mass remains in the original location.

    (a) The plank's velocity (relative to ice) is vpi. The girl's velocity relative to ice is vgp + vpi

    Mp*vpi + Mg(vgp + vpi) = 0
    vpi (Mg + Mp) = -Mg*vgp
    vpi = -[Mg/(Mg+Mp)]*vgp

    (b) vgi = vgp + vpi
    = vgp{1 - [Mg/(Mg+Mp)]}
    = vgp*[Mp/(Mg +Mp)]

    1. 👍 5
    2. 👎 2
  2. THANK U

    1. 👍 2
    2. 👎 0

Respond to this Question

First Name

Your Response

Similar Questions

  1. physics

    A book of mass 7 kg rests on a plank. You tilt one end of the plank and slowly increase the angle of the tilt. The coefficient of static friction between the book and the plank is 0.40. What is the maximum angle of tilt for which

  2. physics

    A 45.0 kg girl is standing on a 163 kg plank. The plank, originally at rest, is free to slide on a frozen lake, which is a flat, frictionless surface. The girl begins to walk along the plank at a constant velocity of 1.45 m/s

  3. Dudas

    John's mass is 86 kg, and Barbara's is 55 kg. He is standing on the x axis at xj = +9.0 m, while she is standing on the x axis at xb = +2.0 m. They switch positions. How far and in which direction does their center of mass move as

  4. physics

    You know that you can safely stand on the hang-over end of a heavy plank that rests on a table. How far depends on your mass and the mass of the plank. Suppose you can stand on the end of a plank that overhangs the edge of the

  1. physics

    A 62kg person lies flat on uniform plank of mass 15kg.The plank, with the person lying on it,is placed on a brick at the head and a bathroom scale at the foot,both under the plank.The persons toe to head dist is 1.56m.The length

  2. science(physics)

    A bullet of mass 100g moving with20m/sec .Strikes a wooden plank and peretrates up to 20cm.Calculate the resistance offered by the wooden plank.

  3. Physics

    Three children are trying to balance on a seesaw, which consists of a fulcrum rock, acting as a pivot at the center, and a very light board 6.0 long . Two playmates are already on either end. Boy A has a mass of 50 , and girl B a

  4. physics

    A uniform wooden plank of length L = 6.0 m and mass M = 90 kg rests on top of two sawhorses separated by D = 1.5 m, located equal distances from the center of the plank. You try to stand on the right-hand end of the plank. If the

  1. Physics - Another Question

    "Two girls, one of mass 40kg and the other of mass 60kg, are standing side by side in the middle of a frozen pond. One pushes the other with a force of 360N for 0.10s. The ice is essentially frictionless. What is each girl's

  2. physics

    A cat walks along a uniform plank that is 4.00 m long and has a mass of 7.00 kg. The plank is supported by two sawhorses, one 0.44 m from the left end of the board and the other 1.60 m from its right end. When the cat nears the

  3. science

    A bullet having a mass of 10g and moving with a speed of 1.5m/s penetrates a thick wooden plank of mass 90g. The plank was initially at rest. The bullet gets embedded in the plank and both moves together. Determine their velocity

  4. Physics

    A book of mass 7 kg rests on a plank. You tilt one end of the plank and slowly increase the angle of the tilt. The coefficient of static friction between the book and the plank is 0.46. What is the maximum angle of tilt for which

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