CourseCourseConceptConceptDocsDocuments

IB Physics HL A 4 9 Hl Angular Momentum Questions

Calculate angular momentum and angular impulse, then apply conservation of angular momentum to rotating bodies with changing speed or mass distribution.

Syllabus
First assessment 2025
Course
Physics HL
Level
HL

Exam points

  • Calculate angular momentum from Iω for rods, point-mass/compound systems and rotating bodies.
  • Apply conservation of angular momentum when no external torque acts, including collisions or changes in mass distribution, to find angular speed or momentum.
  • Calculate angular impulse or change in angular momentum from τΔt and connect it with the change in Iω.

Learn this topic

Study A.4.9 (HL)—Angular momentum conceptsOpen the corresponding Concept lesson for explanations, examples and exam connections.

IB Physics HL A 4 9 Hl Angular Momentum Questions question 1

[Maximum number: 1]

A horizontal rigid bar of length 2 R is pivoted at its centre. The bar is free to rotate in a horizontal plane about a vertical axis through the pivot. A point particle of mass M is attached to one end of the bar and a container is attached to the other end of the bar.

A point particle of mass M3\frac{M}{3} moving with speed v at right angles to the rod collides with the container and gets stuck in the container. The system then starts to rotate about the vertical axis.

The mass of the rod and the container can be neglected.

Figure for Question IB Physics HL A 4 9 Hl Angular Momentum Questions question 1 — IB Physics HL

Write down an expression, in terms of M, v and R, for the angular momentum of the system about the vertical axis just before the collision.

All question bank results loaded