Physics Formulas & definitions Flashcards
acceleration
final velocity-initial velocity/time
mass…
quantity of matter in an object
measured in kg
measured using a balance beam
weight
gravitational pull on an object
measured in newtons
measured using newtonmeter
weight= mass x gravitational field strength
gravitational field strength =…
force/mass
effects of a force
change shape/size of an object
set a resting body into motion
change direction of a moving object
increase/decrease the speed of a moving object
cause a body to wear out
elastic behaviour
where an object can undergo stretching & gain its original shape & size when the force is retracted
plastic behaviour
where an object doesnt regain its shape & size after undergoing stretching
extension of a spring =…
new length-original length
centripetal force
the force that keeps an object moving in a circular path
the force acts perpendicular to the motion of the object
=mv2/t
factors affecting centripetal force
mass of the object
speed “ “
radius “ “
pressure
=force/area
square unit is pascal (pa), its equal to 1 n/m2
pressure in liquid increases with depth, because the further down you go, the greater the weight of liquid above
spring constant (k) =…
force(load)/extension
momentum
is the quantity of motion possessed by a moving body
=mass x velocity
si unit is kgm/s
change in momentum is caused by change in velocity, which is brought about by an external force
change in momentum = final momentum-initial momentum
impulse
change in momentum
force x time
newtons 2nd law of motion
states that the rate of change of momentum is directly proportional to the external force that causes it
newtons 1st law of motion
states that an object remains in its state of rest or motion in a straight line unless it is compelled to change by an external force
newtons 3rd law of motion
for every action there’s an equal and opposite reaction
newtons 2nd law of motion
the rate of change of momentum is directly proportional to the external force that causes it
factors affecting stability
base area
position of centre of gravity
energy
the ability to do work
SI unit is joules
work=
forcexdistance
characteristics of energy
invisible
occupies no space
has no mass or physical properties
can be stored/transformed from one form to another
mechanical transfer
force acting on a body causing it to move
electrical current transfer
from the power source to electrical components
heating transfer
through conduction, convection and radiation
waves
light and sounds are forms of energy which are transferred from place to place
GPE
possessed by a body which is raised above the ground
power=
forcexdistance/time or work/time
efficiency
how well the energy/power supplied to a system is being used
efficiency=
work input/work output X 100
power output/power input X 100
