Car Design Flashcards
Explain a regenerative break system
Put the motor in reverse to slow down the wheels, motor acts as an electrical generator to Convert kinetic energy in to electrical energy which is stored as chemical energy in the battery, so energy is stored and not wasted
Explain how people are injured in a car crash
In a crash you slow down very quickly, so alot of kinetic energy is converted to other forms in a short period of time. This causes a big change in momentum in a short space of time, so people inside the car experience huge, possibly fatal forces.
How are cars designed to convert kinetic energy safely in the event of a crash (4 examples)
Crumple zones- the front and back of the car crumple up on impact, the cars kinetic energy is converted in to other types of energy by the car body changing shape, they increase impact time and so decrease the forces produced by momentum
Side impact bars- strong metal tubes fitted in to car door panels helping direct kinetic energy away from passengers and to other areas eg. Crumple zones
Seat belts- stretch slightly, increasing the amount of time taken for a person to become stationary, and so reducing the forces acting on their chest. The belt also absorbs some of the energy by stretching.
Air bags- slow you down more gradually, decreasing the forces and preventing you from hitting hard surfaces of the car.
Explain What determines the power of a car
The size and design determines the power of a car, the more powerful the engine is the more fuel transferred in to energy per second and so the faster it goes. A higher aerodynamic also also means less air resistance and so allows the car to move faster.
How does a traditional break system work?
Reduce the kinetic energy of a car by transferring kinetic energy in to heat and sound energy
