Final answer:
A physics student realizes that countersteering by pulling back on the right handlebar causes a motorcycle to lean left and turn left, which demonstrates Newton's third law of motion and gyroscopic effects.
Step-by-step explanation:
When a physics student notices that pulling back lightly on the right handlebar of a motorcycle causes the bike to tip to the left and initiate a left turn, this is due to a concept called countersteering. This effect occurs because the action of pulling on the handlebar creates a torque that initiates a lean towards the opposite side. As the motorcycle leans, the tires generate a centrifugal force, causing the motorcycle to turn towards the lean. This is a direct application of Newton's third law of motion: for every action, there is an equal and opposite reaction.
Gyroscopes used in guidance systems are capable of maintaining the direction of their angular momentum constant even under large forces and accelerations due to gyroscopic stability. The spinning mass of the gyroscope maintains its orientation space due to its angular momentum, and it resists changes in its axis of rotation.