Free AP Physics C lesson

Multiple-Body Systems & Pulleys

This AP Physics C: Mechanics lesson is designed for AP Physics C self-study. It includes 4 video lessons, 8 practice questions, and an estimated completion time of 28 minutes.

Video lessons

  1. Two Newton's 2nd Law Example Problems: Ball Hanging From the Ceiling of a Truck and Crate in a Truck

    Watch on YouTube

  2. Solving Problems Involving Multiple-Bodies Using Newton's Laws

    Watch on YouTube

  3. Atwood's Machine Problems

    Watch on YouTube

  4. Atwood's Machine Problems (part II)

    Watch on YouTube

Practice covered

  1. A truck accelerates forward at 2 m/s^2. A crate of mass 10 kg rests on the truck bed. If the crate does not slip, what is the magnitude of the static friction force on the crate?
  2. A ball hangs from the ceiling of a truck by a string. When the truck accelerates forward, the string makes an angle with the vertical. Which force provides the horizontal component needed for the ball's acceleration?
  3. Two blocks are pushed along a frictionless surface by a force of 20 N to the right. Block A has mass 2 kg and block B has mass 3 kg. What is the force that block A exerts on block B?
  4. When solving a multiple-body problem, which approach is most effective?
  5. An Atwood machine has a 5 kg mass on one side and a 3 kg mass on the other side. What is the magnitude of the system's acceleration (in m/s²)? Use g = 10 m/s^2.
  6. In an Atwood machine, which statement is TRUE about the tension in the string (assuming a massless, frictionless pulley)?
Loading your progress...