forces and motion definition

the rate of change of velocity. can be calculated from the gradient of a velocity time graph

acceleration

the distance a vehicle travels under the braking force.

can be affected by road and weather conditions as well as the condition of the vehicle

braking distance

when a force acts on a moving object or on an object that has the ability to move, a change of momentum will occur. The force is equal to the rate of change of momentum.

changes of momentum?

a measure of how far an object moves. it doesn’t depend on direction and is a scalar quantity

distance

the force beyond which an object will no longer deform elastically and will instead deform plastically.

elastic limit

a resistive contact force that acts to oppose the relative motion between two surfaces

friction

the extension of a spring is directly proportional to the force applied to it up to the limit of proportionality

the constant is known as the spring constant

Hooke’s law?

the point beyond which the extension of an elastic object is no longer directly proportional to the force applied to it.

limit of proportionality

the turning effect of a force, equal to the product of the magnitude of the force and the perpendicular distance from the pivot to the line of action of the force

moment

the product of an object’s mass and velocity

momentum

if a stationary object resultant force is 0 the object will remain stationary.

if a moving object resultant force is 0 the object will move at a constant velocity

newton 1st law?

an object’s acceleration is directly proportional to the resultant force acting on it and inversely proportional to the object’s mass.

newton 2nd law?

the forces that two object exert on each other when they interact are = and opposite

newton 3rd law?

for an object in equilibrium the sum of the clockwise moments about any point on the object must equal the anticlockwise moments about the same point

principle of moments?

a measure of a spring’s stiffness. the higher the spring constant the smaller the extension is for a given force.

spring constant?

the sum of the thinking and braking distance

stopping distance

the maximum velocity an object can reach when falling through a fluid. occurs when the resistive forces = the object’s weight

terminal velocity

the distance a vehicle travels during the driver’s reaction time. reaction time can be affected by tiredness drugs or alcohol

thinking distance?

the force acting on an object due to gravity. = to the product of the object’s mass and gradational field strength at it’s location.

weight?