1. C

    Elastic Collision in One Dimention

    I was told that my percentages of discrepancy are wrong for this problem. I felt like that was the easiest and most straightforward part of the problem, so I am wondering if I did anything else wrong. I was told that all of my answers were correct (except the predictions, no feedback) besides...
  2. C

    Elastic catenary sag

    Hi, I would like to ask about the difference of sag elastic and non-elastic catenary. I have string with horizontal tension Th, unit weight w, modulus of elasticity E, cross section A and span length a. Non-elastic catenary (with parameter of catenary c = Th/(w*g)) has a maximum sag sn. When I...
  3. J

    Motion with elastic potential energy and other forces

    Hi everybody, I have been working on a problem foe some time now and I am no nearer the solution as I was at the start. I hope somebody can help. PROBLEM A 15.0 kg stone slides down a snow-covered hill leaving point A (at the top of the hill) with a speed of 10.0 m/s. There is no friction...
  4. A

    Momentum and elastic collisions

    A particle of mass m, travelling at a velocity u, makes a perfect elastic collision with a stationary particle. After the collision both particles are observed to be travelling in directions making angles of 30 degrees to the original path of the first particle. Use the laws of conservation of...
  5. S

    Thermodynamics study of a vertical spring with a mass (Elastic penduluum)

    Hi, I have an elastic penduluum (light spring with a calorific capacity Cl, with a mass m attached on his lower end with a capacity C) attached in a cylindrical container on the upper side (a vertical elastic penduluum) , vacuum is in this cylinder . We have to compute the difference of his...
  6. J

    Is this spring elastic problem erroneous?

    1. Elastic potential energy in a spring is directly proportional to the square of the displacement of one end of the spring from its rest position while the other end remains fixed. If the elastic potential energy in the spring is 100J when it is compressed to half its rest length, what is its...
  7. P

    Maximum elastic energy in rope

    May someone please help me sort this out? I am trying to find out whether a person weighing 784.8 N could survive the fall, given that the initial length of the cord (L0) is 2 m, the person falls 4 m down, the diamater of the cord is 10.5 mm, and pi*diameter^2*Y (=Young modulus) is known to...
  8. T

    Elastic Collision Problem

    A cart with mass 0.340 kg moving on a frictionless linear air track at 1.2 m/s strikes a second cart of unknown mass at rest. The collision between the two carts is elastic. After the collision, the first cart continues in its original direction at 0.66 m/s. a) What is the mass of the second...
  9. T

    Elastic Potential Energy Problem

    A spring with a force constant of 35o N/m is compressed 12 cm by a 3.0 kg mass. How fast is the mass moving after only 10 cm of the spring is released? I don't get how to use the 10 cm part.
  10. T

    Elastic Potential Energy Problem

    A 1.2 kg spring laboratory cart is held against a wall. The spring constant is 65.0 N/m. The spring is compressed 8.0 cm when held against the wall. What is the compression of the spring when the cart's velocity is 42.0 cm/s? I used (1.2)(0.42)^2=65(x)^2 x=5.71 cm But the answer says...
  11. S

    Pls check my work - Fmax in an elastic collision.

    Hi, I've been trying to solve this problem but cant find a formula from a reliable source. A 60g ball is thrown in a path perpendicular to a wall at a velocity of 35m/s. The ball bounces back along the same path without any significant loss of speed. What is the Fmax, the maximum magnitude of...
  12. B

    Lagrangian density of linear elastic solid

    I need the general expression for the lagrangian density of a linear elastic solid. I haven't been able to find this anywhere. Thanks.
  13. K

    Elastic properties affecting momentum transfer

    I posted this on another forum but drew a blank, so either it's trickier than I thought or less interesting than I thought. Remember those executive toys that were popular in the '80s? You have a steel ball on the end of a thin rod hitting another steel ball that is stationary. As near as we can...
  14. W

    Momentum help

    So, this might be an easier problem, but here goes: A moving object has a kinetic energy of 148 J and a momentum of 32.2 kg·m/s. a) Find the speed of the object. b) Find the mass of the object. I know that KE = (1/2)mv^2, but even if i plugged in the numbers, i would end up with two...
  15. O

    Elastic string question

    A bungee-jumping athlete of mass 72 kg leaps from a 40-meters tall bridge, held by an elastic string with elastic constant 100 N/m. What is the maximum string's length so that the athlete arrives at the floor with null speed? Consider that Hooke's law is valid for the string and g = 10 m/s^2...
  16. K

    Elastic Collision of Two cars

    Hey there! So, I've got this sample exam that I'm working my way through, and I'm stuck on a few questions, but this one is particularly frustrating me: A careless driver rear-ends a car that is stopped at an intersection. Just before the collision, the driver slams on his brakes, locking the...
  17. A

    Elastic Collision

    BAC is a smooth rail in a vertical plane : Part BA is circular of center O and radius 50cm , and AC is horizantal . A spring of constant K=500 N/m is placed on the horizontal part AC and its end is fixed at C. A Ball of mass m = 2 kg is placed pn the horizontal part AC. m is pushed towards the...
  18. C

    Elastic Collision

    A 0.24kg object traveling rightward at 3.5m/s collides head-on and elastically with a 0.40kg object traveling leftward at 2.1m/s. What are their velocities after the collision? If the objects are in contact for 0.010s during the collision, what is the magnitude of the average force that they...
  19. N

    a elastic spring question

    A linear elastic spring is 0.15m long. When the upper end is held in the hand and a 0.5kg mass is suspended from the lower end, its length becomes 0.220m. If the hand is now jerked quickly upward, the spring first extends to a length of 0.285m, then the mass starts to move up. The hand is then...
  20. R

    Elastic Collision Problem

    A 10.0 g object moving to the right at 25.0 cm/s makes an elastic head-on collision with a 15.0 g object moving in the opposite direction at 33.0 cm/s. Find the velocity of each object after the collision. My attempt at this problem has been to set the mass of the small object times that...