Recent content by Joules6626

  1. J

    A satellite fired off a planet's surface

    Can someone please help me with this?
  2. J

    A satellite fired off a planet's surface

    I'm sorry, the integral should be 18/(32R) = 1/r r = 32R/18
  3. J

    A satellite fired off a planet's surface

    Homework Statement A nonrotating spherical planet with mass M and no atmosphere has radius R. A particle is fired off the surface at 3/4 the escape speed. Calculate the farthest distance it reaches from the center of the planet if it's fired of tangentially. Homework Equations l = r x p...
  4. J

    Find Rest Mass of Composite Particle After Collision

    so it would be (mc^2)^2 + (cmv1γ1) + 2mc^2 = (Mc^2)^2 + (cMv2γ2)^2? how would that give me a function of just v2 or M?
  5. J

    Find Rest Mass of Composite Particle After Collision

    E1 = E2 (mc^2)^2 + (cmv1/sqrt(1-v1^2/c^2))^2 = (Mc^2)^2 + (cMv2/sqrt(1-v2^2/c^2))^2
  6. J

    Find Rest Mass of Composite Particle After Collision

    Homework Statement A particle of rest mass m and kinetic energy 2mc^c strikes and sticks to a stationary particle of rest mass 2m. Find the rest mass M of the composite particle Homework Equations E = mc^2 + KE E^2 = (mc^2)^2 + (pc)^2 p = mv/sqrt(1-v^2/c^2) The Attempt at a...
  7. J

    Angular Momentum and Torque Problem

    [PLAIN]http://img3.imageshack.us/img3/1496/96925170.jpg So I used the equation T = RFsin(theta) for both torques. My answer sounds pretty reasonable. Is the force of the brick on the roller just the normal force? (100N) or is there something more to it?
  8. J

    Angular Momentum and Torque Problem

    I wasn't sure where to begin the problem, so I just picked the bottom left corner out of random. I'm still stuck on this problem. If you could help me I'd gladly appreciate it.
  9. J

    Angular Momentum and Torque Problem

    The v is tangential velocity of the roller. L = r x p = r*p_perpendicular So I guess the bottom left corner is not the way to go?
  10. J

    Angular Momentum and Torque Problem

    [PLAIN]http://img842.imageshack.us/img842/8718/42780714.png I think I might be on to something for the force of the brick on the roller, but I get a d/dt in there and I'm not sure what to do. The L was taken about the axis on the bottom left of the brick. As for the force the roller needs to...
  11. J

    Angular Momentum and Torque Problem

    Homework Statement Hi, I'm having a problem with a mechanics question. I'm not really sure where to begin solving the problem. It reads: A lawn roller is 20 inches in diameter and weighs 100 pounds. What horizontal force is needed to pull it over a brick 2 inches high? What is the force of...