Braking An Momentum Flashcards
What’s the name given to the distance of vehicle travels to safely come to a stop after the driver has spotted a hazard
Spotting distance
What is thinking distance
The distance vehicle travels during drivers reaction time
What is breaking distance?
The distance vehicle travels once breaks has been applied
What is the relationship between stopping distance, thinking distance, and breaking distance
Stopping distance equals thinking distance plus breaking distance
Does the speed of a vehicle have a bigger effect on the breaking distance, or thinking distance?
Breaking distance
Which distance is proportional to the speed of the vehicle?
Thinking distance
Which distance increases by an increasing amount of speed increases
Breaking distance
What are three factors that affect breaking distance of a vehicle?
Speed road conditions, condition of tires and brakes
What’s the definition of one joule of work?
Work done when one Newton force causes 1 m displacement
Why does the temperature of a vehicles break increase when the brakes are applied?
Work done by the frictional force between the brakes and the wheels, transfers, energy from the kinetic energy store of the car to the thermal energy store of the brakes
What can happen if the breaking force used to stop vehicle is very large
Brakes may overheat/the car may skid
What is the law of conservation of momentum?
In a clear system, the total momentum before an event is equal to the total momentum after it
What does m^V stand for
Change in momentum
How is the force acting on an object related to its momentum?
Force acting on an object equals rate of change of momentum
What are examples of everyday safety features which work by increasing the time taken for the change in momentum?
Airbags seatbelts, crumble zones in cars, cycle, helmets, crash mats, and gyms cushion surfaces in children’s playgrounds
