Rotating Pencil

Long Description of image: Motion diagram of a rotating pencil as it flies through the air.

The centre of mass of the pencil is marked by a dot throughout its motion through the air. The motion of the pencil has a shape similar to that of a parabola. The motion diagram consists of seven dots numbered 0 to 6 and the dot numbered 3 is at the peak of the parabola.

Long description ends.

Part 1

Explain why the particle model that we use to draw motion diagrams cannot adequately represent the rotation of a pencil as it flies through the air as seen in the figure.

Answer Section

• The particle model tells us about the location of the pencil’s centre of mass, but nothing about its orientation.

• The particle model tells us about the location of the pencil’s centre of mass, but nothing about its weight.

• The particle model tells us about the location of the pencil’s centre of mass, but nothing about its mass.

• The particle model tells us about the location of the pencil’s centre of mass, but nothing about its height above the floor.

Attribution

Problem is licensed under the CC-BY-NC-SA 4.0 license.