Definitions Flashcards
Acceleration
the rate of change of velocity
average speed
the distance travelled over time for the entire region of interest
Braking distance
the distance travelled between the the brakes being applied and the vehicle coming to a stop. It is affected by the vehicle and road conditions
Displacement
the direct distance between an object’s starting position and its ending position. It is a vector quantity and has both magnitude and direction
Explain what is meant by the term Free fall
An object is said to be in free fall when the only force acting on it is the force of gravity
instantaneous speed
the exact speed of the object at a specific given point
Explain what is meant by the term projectile motion
the motion of an object that is fired from a point and then upon which only gravity acts
reaction time
the time taken to process a stimulus and trigger a response to it. It is affected by alcohol, drugs, and tiredness
stopping distance
the sum of thinking distance and braking distance for a driven vehicle
thinking distance
the distance travelled in the time it takes for the driver to react. It is affected by alcohol, drugs, and tiredness
velocity
the rate of change in displacement. It is a vector quantity so has both magnitude and direction
Archimedes principle
the upward force experienced by an object fully or partially submerged in a liquid is equal to the weight of the fluid it displaces
center of gravity
the single point through which object’s weight can be said to act
center of gravity
the single point through which object’s weight can be said to act
center of mass
the single point through which all the mass of the object can be said to act
couple
two parallel and equal forces that act on an object through different lines of action. it has the effect of causing rotation without translation.
drag
the frictional force that an object experiences when moving through a fluid
equillibrium
for an object to be in equilibrium, the resultant force and the resultant moment is to be zero
friction
the resistive force that is produced when there is a relative movement between two surfaces
moment of a force
the product of a force and the perpendicular distance to the line of action from the force to the pivot
moment of a force
the product of a force and the perpendicular distance from the line of action from the force to the pivot
Newton 2nd law
the sum of the forces acting on an object is equal to the rate of change of momentum. It is also expressed as the net force acting on object is equal to the product of the object’s mass and acceleration