3.1: Motion Flashcards
Acceleration
The rate of change of velocity
Average speed
Distance over time for the entire region of interest
Braking distance
The distance travelled between the brakes being applied and the vehicle coming to a stop
Displacement
The direct distance between an object’s starting and ending positions.
It is a vector quantity and so has both a direction and a magnitude.
Displacement-time graphs
Plots showing how displacement changes over a period of time. The gradient gives the velocity. Curved lines represent an acceleration.
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 an object at a specific given point.
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.
Velocity-time graphs
Plots showing how velocity changes over a period of time. The gradient gives acceleration. Curved lines represent changing acceleration.
Velocity
The rate of change of displacement. It is a vector quantity and so has both a direction and a magnitude.
