Physics - Forces and Kinematics Flashcards
what is a force
any interaction that when unopposed will change the motion of an object
(push or pull)
what unit is used to measure force?
newtons N
what are newton’s three laws?
- object motion is uniform until acted on by a force
- the acc. of an object is proportional to mass and form f=ma
- for every action there is an equal and opposite reaction
what are the 9 contact forces?
friction
muscular
tension
norma
drag
air
upthrust/buoyancy
surface
what are the 3 non contact forces?
magnetic
electric
gravitational
non contact vs contact force?
non contact -
doesn’t require physical interaction
contact - object is in contact (push or pull egs)
what is the gravitational force acceleration
9.8m/s square
balanced vs unbalanced force
balanced - both values are the same
unbalanced - one force is larger than the others
are mass and weight the same?
mass is the amount of matter in the object
usually in grams or kgs
weight is the force of gravity pulling down an object
formula to calc weight
weight = mass x gravity measured in newtons
what do speed, distance and time tell us?
speed - tells us how fast something or someone is travelling
distance - showcases how far something has gone
time - how long it takes
what is the formula for speed?
speed = dist/time
how is the position of a particle determined?
particle moving in a straight line is determines by its distance from the origin (fixed point), whether it is to the right or left of the O
right = positive
distance vs displacement
displacement - change in position (vector)
distance - length of change between 2 points (scalar)
velocity vs speed
velocity - rate of change of position with respect to time (vector)
speed - rate at which an object moves (scalar)
