A lumberjack (mass = 104 kg) is standing at rest on one end of a floating log (mass = 234 kg) that is also at rest. The lumberjack runs to the other end of the log, attaining a velocity of +3.18 m/s relative to the shore, and then hops onto an identical floating log that is initially at rest. Neglect any friction and resistance between the logs and the water. (b) Determine the velocity of the second log (again relative to the shore) if the lumberjack comes to rest relative to the second log.

I know that it has to do with conservation of momentum, but I have confused myself with the formula and have no idea how to start working it out.

  1. 👍
  2. 👎
  3. 👁

Respond to this Question

First Name

Your Response

Similar Questions

  1. Physics

    A thin uniform rod has a length of 0.550 m and is rotating in a circle on a frictionless table. The axis of rotation is perpendicular to the length of the rod at one end and is stationary. The rod has an angular velocity of 0.4

  2. Physics Spring

    A mass sitting on a horizontal, frictionless surface is attached to one end of a spring; the other end is fixed to a wall. 1.0 J of work is required to compress the spring by 0.12 m. If the mass is released from rest with the

  3. Physics

    Standing on the surface of a small spherical moon whose radius is 6.30 104 m and whose mass is 8.00 1018 kg, an astronaut throws a rock of mass 2.02 kg straight upward with an initial speed 42.2 m/s. (This moon is too small to

  4. Physics

    A 30-kg child stands at one end of a floating 20-kg canoe that is 5.0-m long and initially at rest in the water. The child then slowly walks to the other end of the canoe. How far does the canoe move in the water, assuming water

  1. physics

    Astronauts in space cannot weigh themselves by standing on a bathroom scale. Instead, they determine their mass by oscillating on a large spring. Supppose an astronaut attaches one end of a large spring to her belt and the other

  2. Physics

    Objects A and B have the same mass of 4.3 kg and are at their melting points. They melt when 4.9 × 104 J of heat is added to A and when 12 × 104 J is added to B. (a), (b) Determine the latent heat of fusion for the substance

  3. Physics

    Kelly is driving a car with a mass of 800 kilograms in a south direction with a speed of 18 meters/second. Dominic is driving a truck with a mass of 1500 kilograms with a velocity of 15 meters/second to the east. They undergo

  4. Physics

    Two people are standing on a 2.2-m-long platform, one at each end. The platform floats parallel to the ground on a cushion of air, like a hovercraft. One person throws a 6.1-kg ball to the other, who catches it. The ball travels

  1. Physics

    A dentist causes the bit of a high-speed drill to accelerate from an angular speed of 1.20 104 rad/s to an angular speed of 3.14 104 rad/s. In the process, the bit turns through 1.92 104 rad. Assuming a constant angular

  2. Physics

    A sunbather lying on a floating raft that experiences no friction with the water gets up and walks to the western end of the raft. While she is walking, how does the center of gravity of the system composed of her and the raft

  3. Physics

    A box slides from rest down a frictionless ramp inclined at 35.0° with respect to the horizontal and is stopped at the bottom of the ramp by a spring with a spring constant of k = 3.50 104 N/m. If the box has a mass of 12.0 kg

  4. physics

    A block of mass 12.0 kg slides from rest down a frictionless 35.0° incline and is stopped by a strong spring with k = 4.00 104 N/m. The block slides 3.00 m from the point of release to the point where it comes to rest against the

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