4.1 Linear motion Flashcards
Define scalar quantity
Quantities that just have size
Define vector quantities
Quantities that have size and direction
Define mass
The quantity of matter the body possesses
Define weight
The gravitational force exerted on an object
How is weight calculated?
Mass x gravity (9.8)
Define distance
The path a body takes as it moves from start to finish
Define displacement
The shortest route in a straight line between the start and finish points
What quantity is displacement?
Vector
Define speed
The rate of change of direction
How is speed calculated?
Distance / time
Define velocity
The rate of change of displacement
How is velocity calculated?
Displacement / time
How is the gradient of a graph calculated?
Change in y axis / change in x axis
Define acceleration
Rate of change of velocity (m/s/s)
How is acceleration calculated?
Change in velocity / time
How is change in velocity calculated?
Final velocity - initial velocity / time
How is momentum calculated?
Momentum (kgm/s) = mass x velocity
What quantity is momentum?
Vector
What are the 2 types of forces?
External - comes from outside the body
Internal - generated by the skeletal muscles
What are the vertical forces?
Weight - the gravitational force exerted on an object
Reaction force - occurs when 2 bodies are in contact with one another
What are the horizontal forces?
Friction - occurs when 2 or more 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
What factors affect friction?
- Surface characteristics
- Temperature of surfaces
- Mass of the sliding objects
What factors affect air resistance?
- Velocity of moving body
- Cross sectional area of moving body
- Shape and surface characteristics
What is net force?
The resultant force acting on a body when all other forces have been considered
