STEM
SY 2024-2025
1ST SEMESTER
PHYSICS DEFINITION (3) Zeroes to the left of the first nonzero digits are not
The main definition of physics is a branch of natural significant; such zeroes merely indicate the position of
science that explains and predicts the interaction the decimal point:
between energy and matter. ● 0.001 C has only 1 significant figure,
● Classical Physics – are the physics that were ● 0.012 g has 2 significant figures.
made before the 20th century. This part of (4) Zeroes to the right of a decimal point in a number are
physics studies things like movement, light, significant:
gravity, and electricity. ● 0.023 mL has 2 significant figures,
○ Mechanics – study of motion as a result ● 0.200 g has 3 significant figures.
of forces. SCIENTIFIC NOTATION
○ Acoustics – study of sound Scientific notation is a form of presenting very large
○ Thermodynamics – deals with the numbers or very small numbers in a simpler form.
relationship between heat and other
forms of energy.
○ Electromagnetism – a branch of
Physics, that deals with the
electromagnetic force that occurs
between electrically charged particles. ACCURACY VS. PRECISION
● Accuracy – refers to how closely a measured
○ Optics – studies the behavior and
value agrees with the correct value. It is how
principles of light
close to the actual value.
● Modern Physics – is the study of physical
● Precision – refers to how closely individual
phenomena that occur at conditions that
measurement agree with one another. It is how
exceed the observable limitations of classical
close the data are to each other.
physics.
○ Relativity, Cosmology, Quantum,
Nuclear
MEASUREMENT
It is a process of comparing an unknown quantity with a
standard.
● Fundamental units are those that are
independent of other variables, such as length,
mass, time, temperature, current, luminous
intensity, and substance quantity.
● Derived units are those that may be stated in QUANTITIES
terms of basic units and are also dependent on ● Scalars are quantities that are fully described
others. by a magnitude (or numerical value) alone.
SIGNIFICANT FIGURES ● Vectors are quantities that are fully described
(1) All nonzero digits are significant: by both a magnitude and a direction.
● 1.234 g has 4 significant figures, DISTANCE VS. DISPLACEMENT
● 1.2 g has 2 significant figures. ● Distance involves the total path length
(2) Zeroes between nonzero digits are significant: traversed by object, while displacement
● 1002 kg has 4 significant figures, involves the length of separation of that object
● 3.07 mL has 3 significant figures. and a reference point.
1
, PHYSICS
○ Distance = total path traveled formed using the two vectors as
■ Distance = Speed × Time adjacent sides. The diagonal of the
d=s×t parallelogram, drawn from the common
○ Displacement = shortest straight-line tail point, represents the resultant
distance between starting and end vector.
points. ○ It is commonly used for adding two
■ ∆x = xf – x0 vectors.
● xf is the Final Position ● Polygon Method (Head-to-Tail):
of Object ○ In this method, vectors are placed in
● x0 is the Starting sequence, such that the head of one
Position of Object vector meets the tail of the next. The
● ∆x is the Displacement resultant vector is drawn from the tail of
of Object the first vector to the head of the last
vector in the sequence.
○ This method is more suited for adding
multiple vectors.
DIMENSIONAL ANALYSIS
Dimensional analysis (also called factor label method or
unit analysis) is used to convert from one set of units to VECTORS ADDITION
another. ● Vectors are in the same direction.
○ When two or more vectors are in the
same direction, their magnitudes are
added directly.
○ Resultant Vector (R) = A+B (if A and
Bare the magnitudes of the vectors).
○ The direction of the resultant vector is
the same as that of the individual
vectors.
○ Ex. Two forces of 5 N and 3 N acting in
the same direction: R= 5N + 3N = 8N
● Vectors are in opposite direction.
○ When vectors are in opposite directions,
GRAPHICAL METHOD
their magnitudes are subtracted.
A graphical method is a technique used to solve
○ Resultant Vector (R) = ∣A−B∣| (taking
mathematical problems, represent data, or illustrate
the absolute value of the difference in
concepts through visual means, such as diagrams,
magnitudes).
graphs, or drawings. In physics and mathematics,
○ The direction of the resultant vector will
graphical methods are commonly used to:
be in the direction of the larger vector.
● Parallelogram Method (Tail-to-Tail):
● Vectors in a right angle
○ This method involves placing two
vectors such that their tails are at the
same point. A parallelogram is then
Z.Sagario | STEM 12 JADE 2