TYPES OF MOTION Speed
What does motion mean?
Types of motion in physics
“A body is said to be in motion,if it changes its position with Velocity
respect to its surroundings.” Acceleration
Surroundings are the places in its neighborhood where various If we observe carefully, we will find that everything in the
objects are present.The state of rest or motion of a body is universe is in motion. However, different objects move
relative.For example,a passenger sitting in a moving bus is at differently. Some objects move along a straight line, some
rest because he is not changing his position with respect to move in a curved path, and some move in some other way.
other passengers or objects in the bus.But to an observer According to this we can say that there are three types of
outside the bus,the passengers and the objects inside the bus motion. Which are given as :
are in motion.Therefore we can defined rest as “A body is said
Translatory motion
to be at rest ,if it does not change its position with respect to its
Rotatory motion
surroundings.”
Vibratory motion
We live in a universe of continual motion. In every piece of
matter, the atoms are in state of never ending motion .We move Translatory motion
around the Earth’s surface, while the earth moves in its orbit
around the sun. The sun and the stars, too, are in motion.
Everything in the vastness of space is in a state of perpetual
motion. Every physical process involves motion of some sort.
Because of its importance in the physical world around us .It is
logical that we should give due attention to the study of
motion. Motion is commonly described in terms of:
Displacement
Distance
Time
“In transnational motion,a body moves along a line without any “Straight line motion of a body is known as its linear
rotation.The line may be straight or curved.”Watch how motion.” linear motion
various objects are moving.Do they move along a straight
line?Do they move along a circle?A car moving in a straight We come across many objects which are moving in a
line has transnational motion.Similarly,an aeroplane moving straight line. The motion of objects such as car
straight is in transnational motion. Translatory motion is
moving on a straight and level road is linear motion.
further divided into linear motion,circular motion and random
motion.
Aero planes flying straight in air and objects failing
vertically down are also the examples of linear
Examples of translatory motion in daily life motion.
Motion of train In the above diagram a boy is sliding in straight line
motion of earth which is the example of linear motion.
motion of birds
Linear motion examples in daily life
motion of insects
motion of aero plane Motion of car on the road
motion of gas molecules Motion of football
Sliding a boy in straight line is the example
Linear motion of linear motion
Circular motion
“The motion of an object in a circular path is known “The disordered or irregular motion of a body is
as circular motion.” A toy train moving on a circular called random motion.” Have you noticed the type of
track . Earth revolving around the sun is the example motion of insects and birds? Their movements are
of circular motion. irregular and disorder. Motion of insects and birds is
random motion. The motion of dust or smoke
A bicycle or a car moving along a circular track
particles in the air is also random motion. The
possesses circular motion.Motion of moon around
Brownian motion of a gas or liquid molecules along a
earth is also example of circular motion.
zig–zag is also an example of random motion.”
Examples of circular motion in daily life Random motion of gas molecules is called Brownian
motion.”
Motion of electron around the nucleus
Motion of toy car on circular track Rotatory motion
Motion of planets around the sun
Random motion
“The spinning motion of a body about its axis is
called its rotatory motion.”
Study the motion of a tap. It is spinning about an axis. “The motion of a body about its mean position is
Particles of the spinning top move in circles and thus known as vibratory motion.”
individual particles possess circular motion. Does the
Consider a baby in a swing as shown in above figure.
top possess circular motion? The top spins about its
As it is pushed, the swing moves back and forth about
axis passing through it and thus it possess rotatory
its mean position. The motion of the baby repeats
motion .An axis is a line around which a body rotates.
from one extreme to the other extreme with the swing.
In circular motion, the point about which a body goes
Motion of pendulum of a clock about its mean
around, is outside the body. In rotatory motion, the
position, is also example of vibratory motion.
lone, around which a body moves about, is passing
Children playing in a sea saw is the example of
through the body itself.
vibratory motion . Besides these examples a baby in a
Examples of rotatory motion in daily life cradle moving to and fro, to and fro motion of the
hammer of a ringing electric bell and the motion of
The motion of the earth about its geographic the string of a sitar are some of the examples of
axis that causes day and night is rotatory vibratory motion. Simple harmonic motion is also
motion. example of vibratory motion
The motion of wheel about its axis and that
of steering wheel are the examples of
rotatory motion.
Vibratory motion
1705, he was knighted by Queen Anne of England,
Isaac Newton making him Sir Isaac Newton.
When Was Isaac Newton Born?
Isaac Newton was born on January 4, 1643, in
Woolsthorpe, Lincolnshire, England. Using the "old"
Julien calendar, Newton's birth date is sometimes
displayed as December 25, 1642.
Isaac Newton’s Discoveries
Newton made discoveries in optics, motion and
mathematics. Newton theorized that white light was a
composite of all colors of the spectrum, and that light
was composed of particles. His momentous book on
Who Was Isaac Newton? physics, Principia, contains information on nearly all
of the essential concepts of physics except energy,
Isaac Newton (January 4, 1643 to March 31, 1727) ultimately helping him to explain the laws of motion
was a physicist and mathematician who developed the and the theory of gravity. Along with mathematician
principles of modern physics, including the laws of Gottfried Wilhelm von Leibniz, Newton is credited
motion, and is credited as one of the great minds of for developing essential theories of calculus.
the 17th century Scientific Revolution. In 1687, he
published his most acclaimed work, Philosophiae
Naturalis Principia Mathematica (Mathematical What Did Isaac Newton Invent?
Principles of Natural Philosophy), which has been
called the single most influential book on physics. In
was closed due to the Great Plague. Legend has it
that, at this time, Newton experienced his famous
inspiration of gravity with the falling apple.
According to this common myth, Newton was sitting
under an apple tree when a fruit fell and hit him on the
head, inspiring him to suddenly come up with the
theory of gravity. While there is no evidence that the
apple actually hit Newton on the head, he did see an
Newton's first major public scientific achievement apple fall from a tree, leading him to wonder why it
was designing and constructing a reflecting telescope fell straight down and not at an angle. Consequently,
in 1668. As a professor at Cambridge, Newton was he began exploring the theories of motion and gravity.
required to deliver an annual course of lectures and
chose optics as his initial topic. He used his telescope It was during this 18-month hiatus as a student that
to study optics and help prove his theory of light and Newton conceived many of his most important
color. The Royal Society asked for a demonstration of insights—including the method of infinitesimal
his reflecting telescope in 1671, and the organization's calculus, the foundations for his theory of light and
interest encouraged Newton to publish his notes on color, and the laws of planetary motion—that
light, optics and color in 1672. These notes were later eventually led to the publication of his physics book
published as part of Newton's Opticks : Or, A treatise Principia and his theory of gravity.
of the Reflections, Refractions, Inflections and
'Principia' and Newton’s Laws of Motion
Colours of Light.
In 1687, following 18 months of intense and
The Apple Myth effectively nonstop work, Newton published
Between 1665 and 1667, Newton returned home from Philosophiae Naturalis Principia Mathematica
Trinity College to pursue his private study, as school (Mathematical Principles of Natural Philosophy),
most often known as Principia. It is said to be the inversely proportional to the square of the distance
single most influential book on physics and possibly between their centers.
all of science. Its publication immediately raised
These laws helped explain not only elliptical planetary
Newton to international prominence.
orbits but nearly every other motion in the universe:
how the planets are kept in orbit by the pull of the
sun’s gravity; how the moon revolves around Earth
Principia offers an exact quantitative description of
and the moons of Jupiter revolve around it; and how
bodies in motion, with three basic laws of motion:
comets revolve in elliptical orbits around the sun.
1) A stationary body will stay stationary unless an They also allowed him to calculate the mass of each
external force is applied to it. planet, calculate the flattening of the Earth at the poles
and the bulge at the equator, and how the gravitational
2) Force is equal to mass times acceleration, and a pull of the sun and moon create the Earth’s tides. In
change in motion (i.e., change in speed) is
Newton's account, gravity kept the universe balanced,
proportional to the force applied.
made it work, and brought heaven and Earth together
3) For every action, there is an equal and opposite in one great equation.
reaction.
Early Life and Family
Newton and the Theory of Gravity Isaac Newton was the only son of a prosperous local
Newton’s three basic laws of motion outlined in farmer, also named Isaac Newton, who died three
Principia helped him arrive at his theory of gravity. months before he was born. A premature baby born
Newton’s law of universal gravitation states that two tiny and weak, Newton was not expected to survive.
objects attract each other with a force of gravitational When he was 3 years old, his mother, Hannah
attraction that’s proportional to their masses and Ayscough Newton, remarried a well-to-do minister,
Barnabas Smith, and went to live with him, leaving
young Newton with his maternal grandmother. The relativity. In 1921, he won the Nobel Prize for physics
experience left an indelible imprint on Newton, later for his explanation of the photoelectric effect. In the
manifesting itself as an acute sense of insecurity. He following decade, he immigrated to the U.S. after
anxiously obsessed over his published work, being targeted by the Nazis. His work also had a
defending its merits with irrational behavior. major impact on the development of atomic energy. In
his later years, Einstein focused on unified field
At age 12, Newton was reunited with his mother after
theory. With his passion for inquiry, Einstein is
her second husband died. She brought along her three
generally considered the most influential physicist of
small children from her second marriage.
the 20th century.
Albert Einstein
Who Was Albert Einstein? Albert Einstein’s Inventions and Discoveries
Albert Einstein (March 14, 1879 to April 18, 1955) As a physicist, Einstein had many discoveries, but he
was a German mathematician and physicist who is perhaps best known for his theory of relativity and
developed the special and general theories of
the equation E=MC2, which foreshadowed the the speed of light squared (C2). This equation
development of atomic power and the atomic bomb. suggested that tiny particles of matter could be
converted into huge amounts of energy, a discovery
Theory of Relativity
that heralded atomic power. Famed quantum theorist
Einstein first proposed a special theory of relativity in Max Planck backed up the assertions of Einstein, who
1905 in his paper, “On the Electrodynamics of thus became a star of the lecture circuit and academia,
Moving Bodies,” taking physics in an electrifying taking on various positions before becoming director
new direction. By November 1915, Einstein of the Kaiser Wilhelm Institute for Physics from 1913
completed the general theory of relativity. Einstein to 1933.
considered this theory the culmination of his life
Family
research. He was convinced of the merits of general
relativity because it allowed for a more accurate Albert Einstein grew up in a secular Jewish family.
prediction of planetary orbits around the sun, which His father, Hermann Einstein, was a salesman and
fell short in Isaac Newton’s theory, and for a more engineer who, with his brother, founded
expansive, nuanced explanation of how gravitational Elektrotechnische Fabrik J. Einstein & Cie, a Munich-
forces worked. Einstein's assertions were affirmed via based company that manufactured electrical
observations and measurements by British equipment. Albert’s mother, the former Pauline Koch,
astronomers Sir Frank Dyson and Sir Arthur ran the family household. Einstein had one sister,
Eddington during the 1919 solar eclipse, and thus a Maja, born two years after him.
global science icon was born.
Einstein’s Wives and Children
Einstein’s E=MC2
Albert Einstein married Milena Maric on Jan. 6, 1903.
Einstein’s 1905 paper on the matter/energy While attending school in Zurich, Einstein met Maric,
relationship proposed the equation E=MC2: energy of a Serbian physics student. Einstein continued to grow
a body (E) is equal to the mass (M) of that body times closer to Maric, but his parents were strongly against
the relationship due to her ethnic background.
Nonetheless, Einstein continued to see her, with the
When and Where Was Albert Einstein Born?
two developing a correspondence via letters in which
he expressed many of his scientific ideas. Einstein’s Albert Einstein was born on March 14, 1879 in Ulm,
father passed away in 1902, and the couple married Württemberg, Germany.
thereafter.
That same year the couple had a daughter, Lieserl,
who might have been later raised by Maric's relatives
or given up for adoption. Her ultimate fate and
whereabouts remain a mystery. The couple went on to
have two sons, Hans and Eduard. The marriage would
not be a happy one, with the two divorcing in 1919
and Maric having an emotional breakdown in
connection to the split. Einstein, as part of a
settlement, agreed to give Maric any funds he might
receive from possibly winning the Nobel Prize in the
future.
During his marriage to Maric, Einstein had also begun
an affair some time earlier with a cousin, Elsa
Löwenthal. The couple wed in 1919, the same year of
Einstein’s divorce. He would continue to see other
women throughout his second marriage, which ended
with Löwenthal's death in 1936.
