physics and cars - Sp2 Flashcards
what is thinking distance?
the distance the car travels while the driver reacts to a situation on the road
What is braking distance?
The distance the car has travelled from the moment the breaks have started working to the point of coming to a halt
what is reaction time?
the time between a person detecting a stimulus and their response to it
What factors effect reaction times?
tiredness
if driver is ill
driver has taken drugs
driver has drunk alcohol
driver is distracted (with mobile phone etc)
what do car brakes use to slow the car down?
friction
what factors effect braking distance?
worn breaks, wet roads, loose gravel in roads, tyres are worn, mass of car
how does mass effect braking distance?
more mass needs more force to be able to decelerate
what is transferred between force and an object as the object accelerates
energy
what is work done?
the energy transferred by a force acting over a distance
what is the equation for work done?
force (N) x distance moved in the direction of the force (m)
what are crumple zones?
areas in the front and back of cars that are designed to crumple so the deceleration and the force on the car is less - crumple zones also reduce force on passengers
what happens to force in car crashes where the vehicle must come to a stop very fast
the force needed to decelerate at such a high rate will be large
