P2 - Car Designs And Safety Flashcards
What do regenerative car braking systems do?
Use the energy transferred when applying the brakes.
How do regenerative brakes work?
By using the system that drives the car to do the braking.
What do regenerative braking systems do to the kinetic energy of the vehicle?
The brakes put the motor into reverse which slows the wheels.
What does the motor do when running backwards in a regenerative braking system?
Converts kinetic into electrical energy, which is stored as chemical energy in the battery.
What are car crumple zones?
Areas of the car that crumple on impact.
How do car crumple zones work?
They convert kinetic energy into other forms as the body changes shape, increasing the impact time.
What are side impact bars on a car?
Strong metal tubes in door panels.
How do side impact bars help in a car crash?
They direct the kinetic energy of the crash away from the passengers.
How do seat belts help in a car crash?
They increase the time taken for the wearer to stop, reducing the forces in the chest.
What happens to the kinetic energy of someone wearing a seat belt during a car crash?
It is absorbed by the seatbelt stretching.
How do air bags help during a car crash? [2]
They slow you down gradually & prevent you hitting hard surfaces.
What does the power of a car depend on? [2]
The size & design of the engine.
What does a more powerful car engine do?
Transfer more energy from fuel per second.
What do more powerful cars have?
A higher top speed.
How are cars shaped and why?
Aerodynamically to minimise air resistance.
