P10 Flashcards
What is braking distance?
The distance travelled by a vehicle during the time it takes for its brakes to act.
What is conservation of momentum?
In a closed system, the total momentum before an event is equal to the total momentum after the event.
What does it mean for momentum to be conserved?
Momentum is conserved in any collision or explosion, provided no external forces act on the objects that collide or explode.
What is meant by directly proportional?
A graph will show this if the line of best fit is a straight line through the origin.
What is an elastic material?
A material is elastic if it is able to regain its shape after it has been squashed or stretched.
What is extension in the context of materials?
The increase in length of a spring (or a strip of material) from its original length.
What is gravitational field strength, g?
The force of gravity on an object of mass 1 kg (in newtons per kilogram, N/kg). It is also the acceleration of free fall.
What is inertia?
The tendency of an object to stay at rest or to continue in uniform motion.
What is the limit of proportionality?
The limit for Hooke’s law applied to the extension of a stretched spring.
What is mass?
The quantity of matter in an object – a measure of the difficulty of changing the motion of an object (in kilograms, kg).
What is momentum?
This equals mass (in kg) x velocity (in m/s).
What does Newton’s second law of motion state?
The acceleration of an object is proportional to the resultant force on the object, and inversely proportional to the mass of the object.
What is stopping distance?
The distance travelled by the vehicle in the time it takes for the driver to think and brake.
What is terminal velocity?
The velocity reached by an object when the drag force on it is equal and opposite to the force making it move.
What is thinking distance?
The distance travelled by the vehicle in the time it takes the driver to react.
What is weight?
The force of gravity on an object (in newtons, N).
