Final answer:
A motorcycle turns left when the right handlebar is pulled back due to the gyroscopic effect, where angular momentum causes the bike to lean to the opposite side of the applied force. The Doppler effect describes the change in pitch of a motorcycle as it passes a stationary observer, with the change being more noticeable with higher speeds and closer distances. In a collision, a motorcycle can impart momentum to a van if it strikes with sufficient force.
Step-by-step explanation:
Explaining Motorcycle Dynamics and the Doppler Effect
When a physics student driving a motorcycle at highway speed lightly pulls back on the right handlebar, the motorcycle tips to the left, resulting in a left turn. This occurs due to the gyroscopic effect, which involves the vector aspects of angular momentum. Steering the handlebar to the right initially creates a torque that generates a gyroscopic precession, causing the bike to lean and turn to the left due to angular momentum's perpendicular nature to the applied force.
The Doppler effect is another physical phenomenon experienced by riders. As a motorcycle moves past a stationary observer, the pitch of its sound appears to change from high to low. This shift in frequency is more dramatic the closer and faster the motorcycle moves relative to the observer, exemplifying the Doppler effect.
Regarding collision theory, if a motorcycle were to hit a van with sufficient speed, the transfer of momentum from the motorcycle to the van would cause the van to move. The impact force applied depends on the mass and velocity of the motorcycle and the overall dynamics of the collision.