- Gather Data, find patterns, make a hypothesis, make a prediction, gather data again.
Observation & Experimentation (placebo, control group, blind/double blind)
Testing new medicine - sugar pill - psychological impact - neither group knows if you're getting medication. *measure both groups
Person giving medication doesn't know what pill is which, so they don't act differently when administering the medication
In the gathering data step of the scientific method, both observations and experiments must be performed?
A tentative explanation of some regularity of nature, based on patterns in data.
A thoroughly tested explanation of basic natural phenomena.
Law of Nature
A concise statement or mathematical equation about a fundamental relationship or regularity of nature.
A hypothesis is...
A tentative explanation for a natural phenomenon
A statement, made in advance, about what one believe will happen or how a particular system will behave - in the scientific method - the prediction is based on the hypothesis
The scientific method, which is very useful in many fields besides science, is simply...
A systematic way of evaluating evidence
Use of vague, exaggerated or untestable claims, or untestable claims
Mechanics is concerned with:
The behavior of physical bodies when forces act on them. The effect of moving bodies on their environment.
regular and predictable, the universe is not random. It moves in regular, predictable ways.
Ptolemy - geocentric model of universe, copernicus - heliocentric model of universe, Kepler and Brahe - elliptical orbits
Ptolemaic and Copernicus systems assumed?
All orbits are circular
Branch of physics that deals with the motion and the forces that act on them
The description of motion - Galileo
The explanation of motion - Newton
the distance an object travels per unit time: s=d/t
speed with a direction
the change in velocity of an object per unit time - a=v2-v1/t2-t1
no change in speed or direction
a change in speed or direction - that is, a change in velocity
Galileo's experiments showed?
All objects fall at the same rate regardless of their mass and the velocity of a falling object that starts from rest is proportional to the length of time that it has been falling: v(m/s)=a(m/s2)xt(s)
Distance is proportional to:
the square of the time traveled d=1/2xaxt2
Earth's gravitational acceleration
motion of falling objects
why things move
Newtons 1st law of Motion:
every object continues in its state of rest, or in uniform motion, unless it is compelled to change that state by forces impressed upon it.
The greater the force,
the greater the acceleration. a=f/m or f=m*a
Newton's 2nd law of Motion:
The acceleration produced on a body by a force is proportional to the magnitude of the force and inversely proportional to the mass of the object
Newton's 3rd law of Motion:
between any two objects, there is an attractive force proportional to the product of the two masses divided by the square of the distance between them f=gm1m2-d2