11.1 linear motion Flashcards
scalar quantity
measurements are in terms of size
mass, distance, speed
vector quantity
measurements are described in size and direction
weight, acceleration, displacement, velocity and momentum
mass
quantity of matter the body possesses
weight
mass x gravity (9.8)
newtons
distance
length of path the body takes
metres
displacement
length of straight line joining start and finish
metres
speed
rate of change of distance
speed (m/s)= distance/ time
velocity
rate of change of displacement
displacement/time
acceleration
rate of change of velocity
change in velocity/time
change in velocity= final velocity-initial
reaction force
when two bodies are in contact with one another
for every action there is an equal and opposite reaction
friction
when two or more bodies are in contact with one another
static- no movement between
sliding- movement occurs
air resistance
force that acts in the opposite direction to the motion of a body travelling through the air
depends upon- velocity, surface area, shape
net force
resultant force acting on a body when all other forces have been considered
balanced force
two or more forces acting on body are equal in size but opposite in direction
no change in state of motion
unbalanced force
one force is bigger than the other, creating acceleration
e.g. jumping
