Question Constellation Sign up for free

AQA · GCSE · Physics · Higher

Interlocking Gears and Rotation

Q02.7 2 marks

There are some toy gears on the front of the baby walker. Figure 6 shows the gears.

Figure 6
Figure 6

Figure 6

Enlarged question image

Figure 6

The child applies a force to gear A. This causes a moment about the pivot, so gear A rotates.

Explain what happens to gear B when the child applies the force to gear A.

Write your answer first. You can study the marking guidance whenever you need it.

Answer this question
Study the marking See what earns credit and compare it with a full-mark answer.

Marking points

  1. 1 Gives one credited effect: opposite direction, clockwise rotation, or faster rotation than gear A.
  2. 2 Explains that gear A exerts a force on gear B or produces a moment about B's pivot.

Full-mark answer

Gear B rotates clockwise, opposite to gear A, because gear A exerts a force on gear B and creates a moment about gear B's pivot. Since B is smaller, it also rotates faster than A.

Why this answer loses marks

Gear B turns because it is touching gear A.

This is too vague for either marking point: identify the force or moment and one credited rotation effect.

Answer this question