The product of the
exponent and the
percentage uncertainty
Types of
error
Systematic: due to
system or apparatus
Random: due to
uncontrollable factors
Vectors
Physical
quantities with
magnitude and
direction
Scalars
Physical quantities
with only magnitude
Mechanics
Kinematics
Uniform motion
linear trajectory and
constant velocity
Velocity is the rate of change
of position
Uniformly
accelerated
motion
Acceleration
change of velocity
per unit time
Linear trajectory and
constant acceleration
Forces and
dynamics
Force
First Law of
Newton
An object will remain in its
state of motion, at rest or with
constant velocity, unless and
external unbalanced force is
applied to it
Second Law of Newton
The acceleration of an object is
inversely proportional to its
mass and directly proportional
to the net force applied to it
The force applied on an
object is the rate of
change of momentum
Momentum = mass times velocity
Impulse is the change of
momentum or the force applied on
an object times the time interval in
which it is applied.
Conservation of momentum
The momentum of an isolated
system remains constant
Third law of Newton
When an object exerts a
force on another object, the
second object will expert a
force equal in magnitude but
in opposite direction to the
first object
Work, energy
and power
Energy is the ability to do work
Work is transfer of Energy
Power is the rate at which
work is done or rate at
which energy is transferded
Work = force times
the displacement of
an object
Potential energy =
force of gravity times
hight of an object
Kinetic energy =
(1/2)(m)(v^2)
Conservation on energy
Ideal
Energy is not lost by
heat to surrounding
Not ideal
Energy is lost as heat
to the surroundings
Uniform
circular motion
Centripetal acceleration:
acceleration towards the center
Centripetal acceleration =
(v^2)/(radius)
Centripetal force: sum of
all forces towards the
center.
Angular displacement: Change
of angle during a rotation
Angular velocity: angular
displacement over time
Frequency: number of
revolutions per unit time
Time is the time
needed for one
revolution
Thermal
Heat (Q) is the transfer of
energy
Change of temperature
Heat capacity (C) is the energy
needed to raise the temperature
of an object by 1º C
Specific heat capacity (c) is the energy
needed to raise the temperature of a
material by 1ºC per 1 kg of the material
c=(heat)/(mass times change of temperature)
Change of phase
Latent heat capacity: energy needed
to change of phase per unit mass
Latent heat of fusion (Lf): energy
needed to change from solid to
liquid per unit mass
Latent heat of
evaporation:
energy needed to
change from
liquid to gas per
unit mass
Evaporation
Boiling
Happens only at boiling point and
in all molecules of the object
Happens all the time and only
in molecules of the surface
Oscillations and waves
Simple Harmonic Motion
Conditions: Acceleration must be
proportional to the displacement
from equilibrium position and
acceleration is always directed
toward equilibrium point
When starting at maximum
negative, displacement is
negative; velocity is positive,
but zero; and acceleration is
at its maximum.
When starting from maximum
positive, displacement is
positive; velocity is negative
and zero; acceleration is at its
maximum
Characteristics
Amplitude: maximum displacement
of the object from eq. position; Eq.
position: position when the system
is at rest; Time period: time it takes
for one cycle; Frequency: number of
cycles per unit time.
Waves: disturbance that
propagates through a medium
Pulse: when
disturbance is just once
Traveling wave: continuous
disturbance that propagates
energy
Stationary: static; they do
not propagate energy
Transversal:
Displacement of medium
is perpendicular to the
propagation of energy
Longitudinal: Displacement
of medium is parallel to the
propagation of energy
sound
Velocity: around 340 m/s;
cannot be polarized; can be
difracted in big openings;
refraction: more in solids
Light
Speed = 3x10^8 m/s; can be
polarized; can be difracted; can
be reflected; can be refracted
Characteristics
Amplitude: Maximum displacement of the
medium from eq. point; period: time for one
cycle to pass through a point; frequency: number of
cycles that pass through a point per unit
time; wavelength: distance bewteen two
consecutive crests in phase; wavespeed:
speed of propagation of a wave.
Properties
Reflection
When the wave hits a
different medium, the wave
bounces back
Refraction
when a wave
passes to another
medium
Difraction
When a wave
encounters an
obstacle
Electric current
Electric current: amount of charges
per unit time
Electric potential difference: work
done to move a charge from one point
to another point per unit charge
Electron Volt:
Energy needed to
move an electron
through a p.d. of 1
volt.
Energy & Power
e.m.f.: Chemical
energy converted to
electric energy per unit
charge
p.d.: Electric energy
converted to thermal
energy per unit charge
Power delivered: amount of
chemical energy converted
to electric energy per unit
time
Power dissipated: amount
of electric energy
converted to thermal per
unit time
Ohm's Law: The electric
current through an ohmic
conductor is directly
proportional to the p.d. across
it, remaining temperature and
other physical quantities
constant.
Voltage = Current times
resistance
Resistance: The
ability of an object
to opose a flow of
current
Resistivity: Ability of
a material to opose
a flow of current