Physics
Deals with the interaction of matter, force, and energy.
Usually involves experiments to support, refute, or validate a hypothesis or a theory.
Physics
started in 1900s with Max Planck’s discovery of blackbody radiation.
Modern physics
All discoveries, principles, and invention prior to 1900.
Deals with macroscopic objects moving at speeds very small compared to the speed of light in a vacuum.
Classical physics
Main Branches of classical physics
Mechanics
Heat and thermodynamics
Optics
Electricity and Magnetism
Wave motion and sound
Deals with motion, force, work, energy, and fluids.
Mechanics
deals with the effects of heat when added to or removed from a system.
Heat & Thermodynamics
Deals with the study of light and its properties
Optics
Deals with phenomena associated with electrical charges, magnetism, and relationship between electricity and magnetism.
Electricity and magnetism
Deals with properties, transmission, and perception of different types of waves.
Wave motion & sound
Main branches of Modern Physics
Nuclear physics
General relativity
Special relativity
Particle physics
Quantum Mechanics
Deals with properties of and the reactions within the atomic nucleus.
Nuclear physics
Tells how matter curves space-time and how the curvature of space-time dictates the trajectory of matter and light.
General relativity
Deals with phenomena associated when an object moves with speeds approaching the speed of light in a vacuum.
Special relativity
Deals with the building blocks of matter called elementary particles.
Particle physics
Deals with the nature and behavior of matter and energy on the atomic and subatomic levels.
Quantum mechanics
is the process of comparing something with a standard
Measurement
Two systems of unit
Metric system
English system
Metric system - MKS system
Meter, Kilograms, Second
English metric - FPS system
Foot, Pound, Second
Is the modern form of the metric system.
It is the system of units that the general conference on weights and measures.
The international system of units
may either be fundamental or derived.
Physical quantities
are the basic quantities that are independent of one another.
Fundamental quantities
7 types of Fundamental quantities
Length
Mass
Time
Thermodynamic temperature
Electric current
Luminous intensity
Amount of substance
are combination of fundamental quantities, example may be defined as distance traveled dived by time.
Derived quantities
4 types of Derived quantities
Acceleration
Density
Work
Energy
are units corresponding to the fundamental quantities.
Base or fundamental units
7 types of base or fundamental units
Meter – length
Kilogram – Mass
Second – time
Kelvin – Temperature
Ampere – Electric current
Candela – Luminous intensity
Mole – Amount of substance
refers to the number of important single digits (0 to 9 inclusive) in the coefficient of expression in the scientific notation.
The number of significant figures in the expression indicates the confidence or precision with which an engineer or scientist indicates a quantity.
is the number of digits in a value, also a ratio, that contributes to the degree of accuracy of the value are significant figures.
Significant figures
Rules in Determining Number of Significant Figures
Non-zero digits are significant.
Zeros in between other digits are significant.
Leading zero are not significant.
is a convenient and widely used method of expressing large and small numbers.
Scientific notation
is any number between 1and 10
N
is the appropriate power of 10.
n
The simplest way to convert one unit to another is to form a conversion ratio (equal to one)
with the desired unit on the numerator and the unit to be converted at the denominator. The original quantity is multiplied or divided just like any ordinary algebraic factors.
Conversion ratio
has some degree of uncertainty because of unavoidable errors.
Measurement
is the deviation of a measured value from the expected or true value
Error
is a way of expressing this error.
measured value = (true ± uncertainty) units
Uncertainty
refers to the closeness of a measured value to the expected or true value of a physical quantity. On the other hand,
is the level of measurement that gives true as well as consistent results (i.e. it has no systematic and random errors) The observed results are in agreement with the true results.
refers to how exactly the calculated value matches the right value.
Accuracy
refers to how closely individual measurements are in accordance with each other.
represents how close or consistent the independent measurements of the same quantity are to one another.
is the closeness of two or more quantities to each other is called precision. The level of measurement that gives the same result when repeated.
Precision
is the number of digits considered to be accurate by the person doing the calculation.
Number of significant figures
as the name suggests, result from unpredictable or inevitable changes during data measurement.
affect the precision of the measurements. These errors may be reduced by increasing the number of trials of a measurement and averaging out the results.
Random errors
on the other hand, usually come from the measuring instrument or in the design of the experiment itself.
Systematic errors
is usually calculated. Percent error is given by the formula
Percentage error
is the measured value.
X
is usually considered in judging the accuracy of a measurement.
Percent error
is a measure of how far apart the different measured values are from each other, and is therefore an indication of precision.
Percent difference
Another way to estimate errors from multiple measurements of physical quantity.
Variance of the set of measurements
measures the squared deviation of each number in the set from the mean.
is a statistical measure that quantifies the spread or dispersion of a set of data points.
It indicates how much individual data points in a dataset differ from the mean (average) value of the dataset.
is a measure of how data points differ from the mean
Variance
is a measure of how far a set of data (numbers) are spread out from their mean (average) value.
means to find the expected difference of deviation from actual value.
Variance
means that all measurements are identical.
Variance of zero
indicates that the values are close to one another, which means they are precise.
Small variance
is the standard deviation.
gi for you bIt is a measure of how diverse or spread out are a set of measurements from their average.
Square root of the variance
Eans that the measurement are very diverse
Large standard deviation
Indicates the range of values witch the measurement is asserted to lie with some level of confidence
Uncertainty
maybe reported as absolute to absolute and relative
Degree of uncertainty
has the same unit as the quantity Itself.
Absolute uncertainty
is dimensionless and is obtained by dividing the absolute uncertainty by the numerical or measured value.
Relative uncertainty or Percent uncertainty
is the smallest value that can be read from any measuring device.
Least count