Final answer:
Pulling back lightly on the right handlebar while driving a motorcycle at highway speed causes the motorcycle to tip to the left and produce a left turn due to the principle of conservation of angular momentum.
Step-by-step explanation:
When a physics student pulls back lightly on the right handlebar while driving a motorcycle at highway speed, it causes the motorcycle to tip to the left and produce a left turn. This happens due to the principle of conservation of angular momentum. When the handlebar is turned to the right, the front wheel of the motorcycle turns slightly to the left. As a result, the contact patch of the tire pushes against the ground at an angle, creating a force that causes the motorcycle to lean to the left.