The Physics of Road Traffic Collisions

Flashcards covering key concepts from the lecture on the physics of road traffic collisions, focusing on friction types, Newton's laws, and the effects of collisions on the human body.

What are the main types of friction discussed in the lecture?

Static friction, rolling friction, and kinetic friction.

What happens when a vehicle loses traction?

A skid occurs when the vehicle loses traction between tyres and the road surface.

What does Newton's First Law state about the motion of objects?

Objects at a fixed velocity prefer to stay at that velocity and will resist efforts to change velocity.

What is static friction caused by?

Static friction is caused by temporary bonds being formed at the molecular level between the points of contact of an object and the surface.

Why is kinetic friction weaker than static friction?

Because the relative motion of the points of contact makes it harder to establish strong attractive molecular bonds.

What is unique about a rolling wheel in terms of friction?

A rolling wheel corresponds to static friction because the tyre and the road surface remain in static contact.

What happens when a skid starts regarding the point of wheel contact?

The same point on the wheel remains in contact with the road surface, corresponding to kinetic contact.

How does inertia affect occupants of a vehicle during a collision?

If unrestrained, their inertia will propel them forward on impact.

What is a coup-contrecoup injury?

It is when the brain is injured at the site of impact and on the opposite side due to movement within the skull.

What role do active head restraints play in collisions?

They use the inertia of the occupant to oppose the effects of whiplash.

How can internal organs be affected during a collision?

Their inertia can cause them to strike against the inner surfaces of the thoracic cavity or cranial cavity.

What is a key concept of rehabilitation from a skid?

It is much more difficult to recover from a skid than it is to initiate one.

What can occur due to the average skull's inertia in a collision?

It can lead to whiplash injuries, especially in rear-end collisions.

What are the different types of whiplash injuries mentioned?

Coup injury, contrecoup injury, and coup-contrecoup injury.