PhySci (4th Quarter) Flashcards
is defined as the ability of an object to change its position with respect to its surroundings in given time.
Motion
is always observed and measured with a point of reference.
Motion
It is an example of motion with uniform acceleration.
Free Fall
The change in velocity with a given time.
Acceleration
the distance travelled of an object in a specific amount of time.
Speed
He was an Ancient Greek philosopher who thought that heavier objects fall faster than lighter ones.
Aristotle
It would be needed to have a constant velocity according to Aristotle.
Force
It is required for violent but not natural motion.
Force
Object in vacuum will fall at the same time because in a vacuum there is nothing. Since there is no air or anything in space, objects that are heavy or light, will fall at the same time.
Galileo
It is not necessarily required for violent motion.
Force
It is not required for object moving at constant velocity.
Force
After 14 centuries since Ptolemy, five noted scientists made important discoveries that gave rise to the birth of modern astronomy.
Nicolaus Copernicus
Tycho Brahe
Johannes Kepler
Galileo Galilei
Isaac Newton
He was a Danish astronomer and nobleman who made accurate observations of the movement of celestial bodies in an observatory built for him by King Frederick II of Denmark in 1576.
Tycho Brahe
He was able to determine the position of 777 fixed stars accurately.
Tycho Brahe
Emperor Rudolf II recommended him to work for him as an assistant. He was born to a poor German family and studied as a scholar at the University of Tübingen in 1589.
Johannes Kepler
He was Brahe’s assistant
Kepler
Eventually, Brahe decided to give all his data to Kepler hoping that he would be able to prove his Tychonic system and put together new tables of astronomical data. This table was known as __________ ______, named after the Roman emperor and was useful in determining the positions of the planets for the past 1000 years and the future 1000 years. This table was the most accurate table that is known to the astronomical world
Rudolphine Tables
Brahe died in what year?
1601
After Brahe died in 1601, Emperor Rudolf II assigned ____as the new imperial mathematician, and all of Brahe’s writings, instruments, and the Rudolphine tables were passed on to him. From Brahe’s data, ____ was able to formulate his laws of planetary motion: the law of ellipses, the law of equal areas, and the law of harmonies.
Kepler
Kepler’s Laws of Planetary Motion (3)
The Law of Ellipses
The Law of Equal Areas
The Law of Harmonies
When Kepler tried to figure out Mars’ orbit, it did not fit the then-famous theory that a planet follows a circular path. He then postulated that instead of a circular path, planets follow an oval or an ellipse orbit.
This orbit matched his calculations and explained the “irregularities” in the movement of Mars.
First law- The Law of Ellipses
The second law, states that when an imaginary line is drawn from the center of the Sun to the center of a planet, the line will sweep out an equal area of space in equal time intervals.
The law describes how fast a planet moves in its orbit. A planet moves fastest when it is nearest the Sun and slowest when it is farthest from the Sun, and still, the same area is swept out by the line in equal amounts of time.
Second Law- The Law of Equal Areas
This law describes that the square of a planet’s orbital period (T2) is proportional to the cube of a planet’s average distance from the Sun (R3). It states that the ratio of the squares of the periods of two planets is equal to the ratio of the cubes of the average distances of these two planets from the Sun.
Third Law- The Law of Harmonies
in an ellipse, the ratio of the distance between the foci to the major axis orbit
Eccentricity
a closed curve for which the sum of the distances from any point on the ellipse to two points inside (called the foci) is always the same.
Ellipse
one of two fixed points inside an ellipse from which the sum of the distances to any point on the ellipse is constant
Focus
the maximum diameter of an ellipse
Major Axis
the path of an object that is in revolution about another object or point
Orbit
the time it takes an object to travel once around the Sun
Orbital Period
Speed at which an object (usually a planet) orbits around the mass of another object; in the case of a planet, the speed at which each planet moves along its ellipse
Orbital Speed
half of the major axis of a conic section, such as an ellipse
Semimajor Axis
It is the tendency of an object to
resist change when in motion or when
at rest. Newton’s first law of motion is
also called ____ ____ ____.
Inertia
law of inertia
A 17th century scientist formulated laws explaining why objects are
moving and why they do not move. It has been known as ____’s Three Laws of Motion.
Sir Isaac Newton
He developed the
first concept of laws
of motion.
Galileo
Developed the concept of motion in terms of velocity (speed
and direction) by using inclined planes.
Galileo
Developed the idea of force that causes motion.
Galileo and Inertia
Determined that the natural state of an object is rest or
uniformed motion.
Galileo and Inertia
Developed the idea that objects resist motion, inertia.
Galileo and Inertia
According to Galileo, objects in motion eventually
stop because of a force called ____.
friction
According to ____, objects in motion eventually
stop because of a force called friction.
Galileo
According to Galileo, objects in motion ____ ____ because of a force called fiction.
eventually stop
It is a force that oppose motion between any surfaces that are touching.
Friction
He was born the
same year Galileo died.
His law of inertia is based
on Galileo’s idea of inertia. He
expanded Galileo’s work and
came up with his Three Laws of
Motion.
Isaac Newton
An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.
Newton’s first law of motion
Sir Isaac Newton came up with his ____ Laws of
Motion.
Three
An object’s inertia depends on its ____.
mass
It is the amount of matter or substance that makes up an
object. It is measured in units called kilogram.
Mass
An object
with a greater mass has a ____ ____ and an object
with a lesser mass will also have a ____ ____.
greater inertia
lesser inertia
an object will stay in place unless something orsomebody moves it.
Inertia of rest
a plate on the table
Inertia of rest
an object will continue at the same speed until aforce acts on it.
Inertia of motion
a rolling ball
Inertia of motion
an object will stay moving in the same direction unless a force acts on it.
Inertia of Direction
a moving car turning right
Inertia of Direction
