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STUDY GUIDE:
PHYSICS
EQUATIONS
Acceleration: a = (v1 – v0 /t) where a = acceleration, v0 = object’s speed at the start,
v1 = the speed after time has passed, and t = time.
Antoine equation: log P = B – A/(C + T) where A, B, and C are experimental constants,
T = absolute temperature, and P = vapor pressure.
Balmer’s Formula: 1/ λ = R[(1/m2) – (1/n2)] where λ = wavelength, R = Rydberg constant,
m and n = positive integers that give the quantum numbers of the states
that occur between the transition and the rise to the line.
Bernoulli’s Law: P + ½ pv2 + pgh = constant where P = static pressure, p = fluid density,
v = velocity of the fluid’s flow, g = gravitational acceleration, and
h = height above the surface.
Capacitance: C = Q/V where C = capacitance, Q = the charge on the capacitor, and V = the
voltage (potential difference) across the plates.
Centripetal force: centripetal force = mv2/r where m = mass of the object, v = the object’s
speed around the circle, and r = the radius of the circle.
Density: D = m/v where D = density, m = mass, and v = volume.
Distance equation: d = st
where d = distance, s = speed, and t = time.
Electrical energy: E = Pt where E = electrical energy, P = power, and t = time.
Electric field strength: E = F/Q where E = electric field strength, F = force, and Q = charge.
Page 2, PHYSICS
EQUATIONS (continued)
Escape velocity from the earth’s surface: v = √2GM/r where v = escape velocity from the
earth’s surface, G = the universal gravitational constant, M = the mass of
the earth (or other planet), and r = the starting distance from the center of
the earth.
Force: f = ma
where f = force, m = mass, and a = acceleration. (This equation is Newton’s
Second Law.)
Free-fall rate: (The distance an object falls in a given time) x – gt2/2 where x = distance the
object falls, g = acceleration due to gravity, and t = the time.
Frequency of a pendulum: f = 1/T where f = frequency and T = the pendulum’s period.
Gravitational field strength: gravitational field strength = gravitational force/mass.
Gravitational potential energy: G.P.E = weight times height (G.P.E. = gravitational potential
energy).
Ideal gas law: pV = (m/M)RT = nRT where p = gas pressure in Pascals, V = volume of the gas
in cubic meters, m = mass of the gas in kilograms, M = molar mass in
kilograms per mole, n = amount of the gas in moles, R = molar gas
constant, and T = gas temperature in Kelvin.
Kinetic energy: Ek = ½ mv2 where Ek = kinetic energy, m = mass, and v = velocity (speed of
the object).
Lens equation: 1/u + 1/v = 1/f where u = distance of the object from the lens, v = distance of
the image from the lens, and f = distance of the focal point from the lens.
Magnification: M = I/O where M = magnification, I = image size, and O = the object size.
Moment of Inertia: I = T/a where I = moment of inertia, T = torque, and a = angular
acceleration.
Momentum: p = mv where p = momentum, v = velocity (speed of the object), and m = mass
of the object.
Ohm’s law: I = V/R or V = IR where I = current, V = potential difference (voltage), and
R = resistance.
Potential energy: P.E. = weight times height.
Page 3, PHYSICS
EQUATIONS (continued)
Power: P = IV where P = power, I = current, and V = voltage.
Power = work(energy)/time
Power = force times distance/time.
Pressure: P = F/A where P = pressure, F = force, and A = area.
Pressure in a stationary liquid: P = P0 + hρg where P = pressure in a stationary liquid mass;
P0 = pressure on the surface, h = distance below the surface, ρ = density of
the liquid, and g = the acceleration of free fall.
Rotational kinetic energy: W = ½ Iw2 where W = rotational kinetic energy, I = moment of
inertia, and w = angular speed.
Torque: T = Ia where T = torque, I = inertia, and a = angular acceleration.
Velocity (speed) v = d/t where v = velocity or speed, d = the straight line distance from the
object’s starting position to its end position, and t = time.
Wavelength: v = fλ where v = velocity, f = frequency, and λ = wavelength.
Weight: W = mg where W = weight, m = mass, and g = acceleration due to gravity.
Work: W = Fd where W = work, F = force, and d = displacement or distance.
The relationship between focal length f of a lens, the object distance p, and the image
distance q is: 1/f = 1/p + 1/q
5 equations of straight line motion where s = displacement in meters, t = time in seconds,
u = initial velocity in meters per second, v = final velocity in meters per second and
a = acceleration in meters per second squared.
s = (u + v/2)t
v = u + at
s = ut + ½ at2
s = vt – ½ at2
v2 = u2 + 2as
To convert degrees Celsius to degrees Fahrenheit: °F = (°C times 9/5) + 32
To convert degrees Fahrenheit to degrees Celsius: °C = 5/9 (°F -32)
Page 4, PHYSICS
BRANCHES OF PHYSICS
acoustics: the branch that studies the production, transmission, characteristics, and effects of
sound.
actinology: the branch that deals with electromagnetic radiation and its effects.
aerodynamics: the study of airflow and its effects on objects moving through the air.
aeronautics: the study of flight through the air.
astrophysics: a branch of astronomy that studies stars and galaxies and applies the laws of
physics to the constellations, star evolution, and the luminosity of stars.
atomic and molecular physics: the study of the structure of atoms, molecules, and the forces
and interactions between them.
ballistics: the branch that studies the motion and behavior of projectiles, bombs, missiles, and
rockets.
biophysics: the branch that studies the application of physics to biological processes and
phenomena.
chromatics: a branch of optics that deals with colors, especially the hue and saturation.
cosmology: the study of the structure and evolution of the entire universe.
cryogenics: the study of low temperatures (almost to the absolute zero level) and the
phenomena that occur at these temperatures.
dynamics: the study of motion, the forces that produce the motion, and the study of
acceleration.
electricity: the study of the behavior of electrical charges and the energy associated with these
electrical fields.
electrodynamics: the study of the interactions between electrical currents and magnetic fields
that have been generated by other electric or magnetic fields.
electrostatics: the study of electric charges at rest.
fluid mechanics: the study of the characteristics, properties, and behavior of fluids (gases
and liquids).
Page 5, PHYSICS
BRANCHES OF PHYSICS (continued)
geophysics: the study of the physical aspects of the earth in the areas of seismology, tidal
conditions, meteorology, oceanography, and terrestrial magnetism.
hydraulics: a branch of engineering that studies liquids at rest and in motion.
hydrodynamics: a branch that studies motion that’s created in a fluid by applied forces, or the
behavior and movement of solid bodies that are immersed in fluids.
hydrostatics: the study of liquids at rest and the forces that act upon them.
mechanics: the study of motion.
nuclear physics: the study of the structure, forces, and reactions of atomic nuclei including such
topics as radioactivity and the atomic bomb.
optics: the study of light, reflection and refraction, lenses and mirrors, and the characteristics and
movements of light waves.
quantum mechanics: the branch that studies both atomic and subatomic systems and their
interactions with radiation.
relativity: a branch of modern physics that deals with objects that are moving at extremely high
speeds that could be compared to the speed of light.
thermodynamics: the study of heat, temperature, gas laws, heat transfer, and heat engines.
Page 6, PHYSICS
THEORIES AND LAWS
Abney Law: The shift in the apparent hue of a color in the spectrum to which white light has
been added is toward the red end of the spectrum if the wavelength is less than 570 nanometers.
It shifts toward the blue end of the spectrum if its wavelength is greater than 570 nanometers.
Amagat Law (or Leduc Law): The volume of a gas mixture is equal to the sum of the volumes
that each gas in the mixture would occupy at the same temperature and pressure as the mixture.
Ampere’s Rule: If a conductor is held with the right hand so that the thumb points in the
direction of the current, the fingers will curl around the conductor in the direction of the
magnetic field.
Archimedes Principle: The buoyant force on an object is equal to the weight of the fluid that’s
displaced by the object.
Atomic Theory (by John Dalton): Each chemical element is composed of single, unique atoms
that can combine to create more complex chemical compounds.
Avagadro’s Law: Equal volumes of different gases at the same temperature and pressure
contain an equal number of molecules.
Bernoulli’s Principle: As the speed of a moving fluid increases, the pressure within that fluid
decreases.
Bernoulli-Euler Law: The curvature of a beam is proportional to the bending movement.
Biot-Savart law: The magnetic induction near a long, straight conductor is directly proportional
to the flow of the current through the conductor and inversely proportional to the distance from
the conductor.
Blondel-Rey law: This law calculates the apparent point brilliance of a flashing light by using
the equation B = Bo[f/(a + f)] where B = the apparent point brilliance of the flashing light,
Bo = the point brilliance during the flash, f = the length of the flash in seconds, and a = a constant
having a value of approximately 0.2 seconds.
Boyle’s Law: The pressure and volume of an ideal gas are inversely proportional.
Charles’ Law: The volume of an ideal gas at constant pressure is proportional to the
thermodynamic temperature (absolute temperature) of that gas.
Clausius Law: The specific heat of an ideal gas does not depend upon its temperature.
Page 7, PHYSICS
THEORIES AND LAWS (continued)
Coulomb’s Law: The attraction or repulsion between two electrical charges acts along a line
between them, is proportional to the product of their magnitudes, and is inversely proportional to
the square of the distance between them. F = (kq1q2)/r2 where F = electrical force between the
charged objects; k = the universal electric constant of free space accepted as 9.00 x 109 N m2/c2);
q’s = the charges; and r = the distance between the charges.
Dalton’s Law: The total pressure exerted by a mixture of gases is equal to the sum of the partial
pressures of the mixed gases.
Darcy’s Law: The rate at which a fluid flows through a permeable substance is equal to the
permeability of the substance through which the fluid flows times the pressure drop per unit
length of flow divided by the viscosity of the fluid.
Einstein’s Theory of Relativity: The laws of physics are identical in all constant frames of
reference and the speed of light is constant, regardless if your state of reference is at rest or at a
constant velocity.
Faraday’s Law of Electromagnetic Induction: The amount of electromotive force that’s
induced in a circuit by a changing magnetic field equals the negative of the rate of change of the
magnetic flux connecting the circuit.
First Law of Thermodynamics: The total energy in a closed system does not change. Any
increase in ∆U in the internal energy of a system is the sum of the heat ∆Q flowing into the
system and the work ∆W that’s done on the system.
∆U = ∆Q + ∆W
Hooke’s Law: The stress applied to an elastic substance is proportional to the strain.
Kirchhoff’s first law: The sum of the electrical currents flowing towards the junction of several
conductors is equal to the sum of the currents leaving the junction.
Kirchhoff’s second law: The net e.m.f. in a circuit loop equals the sum of the differences in
voltage around the loop.
Law of Conservation of Mass (by Antoine Lavoisier): The total mass in a chemical reaction is
constant. Thus, the mass of the products is equal to the mass of the reactants.
Law of Electric Charges: Like charges repel and unlike charges attract.
Lenz’s Law (tells the direction current will flow when a magnet is moved near a coil): The
induced current flows so that its magnetic field opposes the change that produced the current.
Newton’s First Law of Motion: An object at rest tends to remain at rest, and an object in
motion tends to remain in motion unless acted upon by an outside force.
Page 8, PHYSICS
THEORIES AND LAWS (continued)
Newton’s Second Law of Motion: F = ma The greater the force that’s exerted on an object,
the faster the object accelerates. Thus, a greater force is needed to accelerate an object having a
greater mass or inertia.
Newton’s Third Law of Motion: For every action, there is an equal and opposite reaction.
Newton’s Law of Universal Gravitation: There is a gravitational attraction between any two
particles in the universe which is proportional to the product of their masses and inversely
proportional to the distance between them. F = G (m1m2/r2)
Ohm’s Law: The current flowing through a metallic conductor is proportional to the potential
difference between its ends.
Pascal’s Principle: When added pressure is put on a confined liquid, the pressure is transmitted
equally to all parts of the liquid.
Second Law of Thermodynamics: Useful energy is lost when there is a transfer from one form
of energy to another.
Stefan’s Law: The power radiated from a body is proportional to the area of the body, and its
absolute temperature raised to the fourth power. W = σAT4
Torricelli’s Theorem: Any fluid flowing from a hole in an open container will flow at the same
rate that any object would move if it were dropped from the same height as the head of the water
above the opening.
Universal Law of Conservation of Energy: Energy cannot be created or destroyed, but it can
be changed from one form to another.
Page 9, PHYSICS
GENERAL PHYSICS VOCABULARY
abhesive: any substance, such as Teflon, that prevents two substances from adhering.
absorption: The process in which radiant energy waves are taken in and not reflected as they
pass through a medium, thus resulting in a partial energy loss.
acceleration: a change in velocity that occurs when an object speeds up, slows down
(deceleration), or changes direction.
aclastic: having the property of refracting no light.
adhesion: the force that occurs between the molecules of two unlike substances and holds them
together.
adiabatic: an adjective that refers to any change in which heat is neither gained or lost.
alpha particle: A positively charged particle that’s emitted by a radioactive substance. It has
two protons and two neutrons, just like the nucleus of a helium atom.
alternating current: electric current that reverses its direction several times per second.
ampere: the unit of electrical current.
amorphous: lacking a definite shape or form and having no definite crystalline structure.
amplifier: a device that increases the strength of a signal without altering its characteristics.
amplitude: the distance from the top or the bottom of a wave to its center.
angle of deviation: The angle that the incident ray makes with the emergent ray when light is
passed through a spectrum.
angle of incidence: The angle a ray makes with the normal of the surface from which it
is reflecting.
angstrom: A unit of length equivalent to 10-10 meters that’s used mainly to measure
wavelengths of optical spectra.
anomalous viscosity: a liquid whose viscosity decreases as its rate of flow increases.
antinode: the point of maximum destructive interference.
Page 10, PHYSICS
GENERAL PHYSICS VOCABULARY
aperture: a hole or opening through which light is transmitted; the opening where light enters a
camera.
armature: the rotating part of a generator or motor.
atomic number: the number of protons in an atom’s nucleus.
attenuation: loss of energy as the energy travels; a weakening of a group of particles by
anything that’s placed in its path.
Auger effect: the movement of an electron from a less bound shell to an more tightly bound
electron shell, thus transferring energy through electrostatic interaction to another bound electron
that also escapes.
Avagadro’s number: The number of molecules in one mole or 22.41 L of any gas.
(6.022 x 1023 particles)
ballast resistor: a resistor that increases its resistance as the current flowing through it
increases, and likewise decreases its resistance when the current slows.
Barnett Effect: the process in which a ferromagnetic material can be magnetized by rapidly
rotating the object.
Becquerel: a derived unit of radioactive decay in which 1 Becquerel is equivalent to 1
disintegration per second.
Beck hydrometer: a graduated device used for measuring the relative density of liquids that are
less dense than water.
Beranek scale: a scale into which the loudness of a noise is classified as very quiet, quiet,
noisy, very noisy, and intolerably noisy.
beta decay: radioactive disintegration in which either an electron or antineutrino is emitted from
the nucleus at the same time, thus either increasing or decreasing the atomic number by one.
Bingham solid: any material such as modeling clay, that has little tendency to flow until a large
force is applied.
black body: any object or body that absorbs all the heat energy or light radiation that falls on it.
British thermal unit (Btu): the amount of heat energy that’s needed to raise the temperature of
one pound of air-free water from 60 degrees Fahrenheit to 61 degrees Fahrenheit if pressure
remains constant.
Page 11, PHYSICS
GENERAL PHYSICS VOCABULARY (continued)
Brownian movement or motion: the irregular movement of minute particles that are suspended
in a fluid, with the velocity of the particles being proportional to the square root of the
temperature.
buoyancy: an upward force exerted by a liquid on an immersed object.
Calorie: the amount of heat needed to raise the temperature of one gram of water one degree
Celsius; equivalent to 4.18605 joules.
capacitance: the ratio of the change of an electrical charge in a system to the corresponding
change in its electrical potential.
capacitor: a device that stores electric charges.
cathode: the terminal from which current leaves a storage battery.
center of gravity: the point at which all the mass of an object is concentrated.
Coanda effect: the tendency of a moving fluid (gas or liquid) to slow down and attach itself to a
surface that it is flowing over.
cohesion: the attractive force that occurs between molecules of the same type. Surface tension
is caused by the cohesion of the water molecules.
commutator: a device that’s attached to the rotating armature of a motor or generator; the
device that converts the AC of the generator into DC output.
compressibility: the ability to reduce an object’s volume by applying pressure.
concave lens: a lens that is thinner in the middle than at its edges.
conductor: any material through which electrons easily flow.
constructive interference: two or more waves that meet at one point and continue moving
together in phase at the same frequency, thus enhancing one another.
convection: the type of heat transfer that occurs in liquids and gases in which warmer and less
dense molecules rise, thus heating those molecules above them and causing a current within the
fluid.
convex lens: a lens that is thicker in the center than at its edges.
Page 12, PHYSICS
GENERAL PHYSICS VOCABULARY (continued)
Coulomb: the amount of charge that’s created when a current of one ampere flows for one
second; the unit of electrical charge.
creep: the slow change in an object’s shape caused by a small continuous stress applied on the
object over time.
current: the flow of electrons through a conductor.
degradation: the loss of energy of a particle through a collision.
density: the ratio of the mass of an object to its volume.
diffraction: the bending of waves around an object.
diffraction grating: an optical device into which many thin, parallel slits have been cut. When
light strikes the surface, many beams of light are produced that interfere to create spectra.
diffuse reflection: a type of reflection that occurs when light is bounced off a rough surface in
many different directions.
direct current: electrical current that flows only in one direction.
dispersion: the sorting out of waves based upon the speed at which they travel.
dissipation: the loss of energy that occurs when it’s converted to heat energy.
domains: the small molecular structures within a magnet that must be aligned in the same
direction to create a magnetic force.
drag: the frictional force that opposes motion when an object moves through a fluid.
efficiency: the ratio of the useful work done by a machine to the work done by the effort force,
multiplied by 100% and thus expressed as a percentage.
Einstein –de Hass effect: A freely suspended ferromagnetic material begins to rotate when its
magnetization changes.
elastic energy: potential energy that is stored in a distorted object, such as a spring.
electric field: a region of space in which an electric charge will experience a force.
electromagnet: a coil of wire wound around a soft iron or steel core that becomes magnetized
when an electric current is passed through the wire, and demagnetized when the current is
stopped.
Page 13, PHYSICS
GENERAL PHYSICS VOCABULARY (continued)
electromagnetic induction: the process in which a changing magnetic field produces an electric
field, thus transferring electrical power from one circuit to another.
electromagnetic spectrum: an arrangement of electromagnetic waves according to their
wavelength, ranging from radio waves with their long wavelengths to gamma rays with their
short wavelengths. The waves between the two extremes are classified as infrared rays, visible
light, ultraviolet rays and x-rays.
electroscope: a device consisting of two metal leaves suspended inside a closed glass flask that
detects charges.
endothermic: an adjective that indicates that heat is absorbed from the surroundings.
energy: the ability to do work.
equilibrium: a state that occurs when the sum of all the opposing forces on an object or system
equals zero, thus causing the object to remain at rest or to remain in continuous motion with no
acceleration.
escape velocity or escape speed: the speed an object must travel to escape the earth’s gravity
and leave the earth..
exothermic: an adjective that indicates that heat is released into the surroundings.
fission: the splitting of a nucleus into two comparable nuclei, emitting a large amount of energy.
force: a push or a pull.
free fall: the condition in which an object is moving with only gravity’s influence.
frequency: the number of times a second that something occurs.
friction: a rubbing force between objects.
fulcrum: the point on which a lever rests and pivots.
fundamental particles: the three particles that make up all matter: the proton, neutron,
and electron.
fusion: the combining of smaller nuclei to create larger nuclei, thus emitting energy.
galvanometer: a device that measures small electrical currents.
Page 14, PHYSICS
GENERAL PHYSICS VOCABULARY (continued)
generator: a device that uses a rotating coil in a magnetic field to change mechanical energy to
electrical energy.
gravity: a force that occurs between any two objects in the universe.
hadrons: subatomic particles composed of quarks that are held together by exchange particles
called gluons.
half-life: the average time that’s needed for half the nuclei in a radioactive element to decay.
heat of fusion: the amount of heat that is required to change one gram of a substance from a
solid to a liquid state.
heat of vaporization: the amount of heat needed to change one gram of a substance from a
liquid to a gaseous state.
inertia: the tendency of a body at rest to remain at rest, or the tendency of a body in motion to
remain in motion unless acted upon by an outside force.
insulators: materials that do not carry electric charges or allow them to pass through.
intensity: the strength or amount of a quantity.
isotope: an atom of an element that has the same number of protons as another element, but has
a different number of neutrons.
kinetic energy: energy of motion.
lift: the upward thrust on an airplane created by the moving air around the plane.
linear acceleration: the rate of increase or decrease in an object’s speed.
load: any device that consumes electrical power.
longitudinal wave: a wave in which the vibrations of the medium are parallel to the direction
the wave is traveling. (The most common longitudinal wave is a sound wave.)
malleability: the ability of a metal to be hammered into thin, flat sheets.
mass number (atomic mass): the number of protons and neutrons in an atom’s nucleus.
mechanical advantage: the number of times that a machine multiplies the input force.
medium: the object through which a wave moves.
Page 15, PHYSICS
GENERAL PHYSICS VOCABULARY (continued)
microgravity: a state of extremely weak gravity.
miscible: capable of being mixed or combined.
momentum: the product of an object’s mass and velocity.
monomer: a simple molecule that combines with other molecules to form a polymer.
motor: a device that converts electrical energy into mechanical energy.
nuclide: a nucleus in which the atomic number and the atomic mass is known.
occlusion: the adhering of a gas or liquid to a solid, or the trapping of a gas or liquid within a
solid mass.
open circuit: an electric circuit that is broken and thus has no complete path for the electrons.
oscillator: a device that produces alternating current from direct current.
parallel circuit: an electric circuit that has two or more paths for the electrons to follow.
pendulum: a mass (bob) that’s suspended on a string that swings back and forth.
period: a single repetition of a cycle, as in one complete back and forth swing of a pendulum.
permeability: the ability of a membrane or other object to allow materials to pass through.
photons: tiny bundles of energy found in electromagnetic waves.
photovoltaic conversion: a process in which sunlight is converted directly into electricity.
potential energy: energy due to an object’s position.
power: the rate of doing work.
principle of supposition: The disturbance at the point where two waves meet is the vector sum
of the disturbances that would have resulted from the individual waves.
product: a new substance that’s formed during a chemical reaction.
projectiles: objects that are thrown upward into space at an angle and that then fall back to
the earth.
Page 16, PHYSICS
GENERAL PHYSICS VOCABULARY (continued)
quarks: a class of particles that compose protons, neutrons, and other hadrons.
radiation: any electromagnetic wave.
rectifier: a vacuum tube or other electronic device that changes alternating current to
direct current.
reflection: the bouncing of light off a surface.
refraction: the bending of light as it passes from one medium to another.
resistance: the ratio of the potential difference to the current in an electrical circuit; the
opposition that a material provides to a moving charge.
series circuit: an electrical circuit that has only one path for the electrons to follow.
solenoid: a coil of wire with many loops that acts as a magnet when an electrical current is
passed through it.
specific gravity: the ratio of the density of a given substance to the density of water. (The
density of water = 1 gram per cubic centimeter.)
specific heat capacity: the amount of heat that’s needed to raise the temperature of one
kilogram of a material by one degree Kelvin. C = ∆Q/ m times ∆θ
specific latent heat: the amount of heat transferred per unit mass when a pure material changes
state without a temperature change; measured in the units joules/kilograms.
temperature: a measure of heat.
terminal velocity: the point at which a falling object reaches its maximum speed and stops
accelerating.
thermocouple: a device that produces electrical energy from heat energy.
torque (also called a moment): the tendency of a force to cause or change rotational
movement; a vector force that is calculated by multiplying the force by distance, which might be
the length of the lever arm or the radius.
trajectory: the path taken by a free-falling object.
transformer: a device that increases or decreases the voltage of alternating current.
Page 17, PHYSICS
GENERAL PHYSICS VOCABULARY (continued)
transistor: a semiconductor or solid-state device that’s replaced vacuum tubes in the
amplification and control of electronic signals, thus acting as an amplifier, rectifier, or oscillator.
transverse wave: a wave in which the vibrations are perpendicular to the direction the wave is
moving, as characterized by electromagnetic waves.
tritium: the radioactive isotope of hydrogen that has a mass of 3.
trough: the lowest point of a transverse wave.
vacuum: a space in which there is no matter.
valence electrons: the electrons in an atom’s outermost energy level.
viscosity: the resistance to flow in a gas or liquid.
volume: the amount of space occupied by an object.
wave: a disturbance that travels through a medium and changes the matter during the process.
wavelength: the shortest distance between two wave crests or two wave troughs.
Page 18, PHYSICS
STANDARD UNITS OF MEASUREMENT IN THE INTERNATIONAL (SI) SYSTEM:
1. meter: distance, length, linear dimensions
2. kilogram: mass
3. second: time
4. Kelvin: temperature
5. ampere: electric current
6. candela: luminous intensity
7. mole: material quantity
OTHER DERIVED UNITS OF MEASUREMENT:
1. Newton: mechanical force
2. Joule: energy/work
3. watt: power
4. coulomb: electric charge quantity
5. ohm: electrical resistance
6. siemens: electrical conductance
7. hertz: frequency
8. farad: capacitance
9. henry: inductance
10. weber: magnetic flux
11. tesla: magnetic flux density
12. bar: pressure
13. decibel: sound intensity (the loudness of a sound)
14. erg: work or energy
15. volt: electric potential
16. pascal: pressure/stress
17. Becquerel: radioactive decay (activity)
THE FOUR FUNDAMENTAL INTERACTIONS:
1. gravitational interaction: the force that’s present between any two objects.
2. electromagnetic interaction: the force that’s effective between all charged particles;
the main force that accounts for atomic stability and molecular structure.
3. strong interaction: associated mainly with quarks; this strong force counteracts the
repulsive force of the protons in the nucleus and operates during a nuclear reaction.
4. weak interaction: the force that operates during beta decay; the force that controls
hadron and quark decay and transformation events.
THE UNIVERSAL FORCES:
 Gravitational
 Electromagnetic
 Fission
 Fusion