4.1 Linear Motion Flashcards
Scalar quantities
Measurements described in terms of size or magnitude (mass distance and speed)
Vector quantities
Measurements described in terms of magnitude (size) and direction (
Mass
The quantity of matter the body posseses
Weight
Force exerted by an object
Weight = mass x acceleration due to gravity
Measured in newtons
Distance
The path a body takes as it moves from the starting to finishing point (measured in meters)
Displacement
The shortest route in a straight line between the starting and finishing point (measured in meters)
Speed
Distance divided by time
Measured in meters per seconds
No reference to direction
Velocity
Displacement divided by time taken
Measured in meters per second
Acceleration
Change in velocity divided by time
Measured in meters per second squared
Rate of change of velocity
Momentum
Mass (kg) x Velocity (m/s) = momentum (kgm/s)
External force
Comes from outside the body
Internal force
Is generated by the skeletal muscles
Reaction force
Occurs when two bodies are in contact with one another
Air resistance
A force that acts in the opposite direction to the motion of a body travelling through the air
Friction
Occurs when two or more bodies are in contact with one another
