Questions On Kinematics

Submitted By cgunn2013
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`Physucks Study Guide Quiz 1:
1. Things Everyone Should Know
● Units ­ see dimensional analysis and measurement sections
● Kinematics
○ Kinematics is the study of the relationships between quantities that are involved in the study of motion.
○ Motion has to do with: Displacement, Velocity, and Acceleration.
○ Primary notion is that there are forces
○ Forces represent the effect of other bodies on the body whose motion is under study.
○ Energy = m g h
○ Work = Total Energy
● Algebra, Trigonometry, and Analytic Geometry
○ Linearity
○ Solving for various unknowns and equations
○ Trigonometric definitions and functions
○ Angle addition (adding to 180)
○ Analyzing shapes of conic sections lie parabolas, hyperbolas, and ellipses
○ We can also expect him to introduce sophisticated symbols with regards to fields b/c they involve so many variables.
● Number Sense (i.e. Fermi pblms.)
○ Having number skills means ­ having a “sense of quantity” and putting things into context ○ Having the ability to understand the meaning of orders of magnitude
○ Relevant to journalism, public policy, and not being a dumbass in life.
○ Scientific Notation/Exponent Rule: x^a * x^b = x^(a+b)
● Fermi Problems ○ Require simple reasoning and plausible assumptions
○ Base everything off of experience and intuition
○ Accuracy is not the point. Process > Detail
● Mathematics and Physics
○ Mathematics
■ Math is the language we use to describe physical phenomena
■ Objectification of thinking process. It is not a substitute for thinking but it provides a framework in which detail of the thinking process are codified.
○ Causal Agents
■ Force is the first ‘causal agent’ we discuss
■ Effects that can be traced to some articulated source or agent and these effects are articulated for that agent as if the other agents were not present
■ Two types of forces: phenomenological and basic (strong, weak, electromagnetic, and gravitational).
2. What is Physics/Science?
● Observation
○ “The world is a knowable place”
○ Science involves experimentation. Experimentation is the “process of careful observation.” ■ But observation involves measurements; even when you just describe color as
‘red’ you are referencing a wavelength which is a measurable quantity.

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■ Therefore, all science/physics is based on the process of measurement and quantitative observation.
○ The only route to knowledge is through experiment. It doesn’t matter how wonderful your theorizations are, if your results from an experiment differ then the theory must be replaced. ○ Physics→ is the “careful observation of the world followed by development of idealized objects that reproduce this behavior followed by the extension of these ideas until they either fail of their own accord or they are found to no longer agree with the experiment.” ■ Example of theory development: Fermat → Fresnel → Maxwell
● Quantitative
○ Measurement
■ To be measurable, the attribute must satisfy an objective equivalence or reflexive relationship: if A ≥ B and if B ≥ C then A ≥ C
■ Once you have an ordered set, then map that ordering onto the real line. This is all an abstract way to say that then you can assign numeric values and then, a scale. ○ Nano
● Evidence Based Constructs
○ Descriptive
■ Logically Complete
● Mathematics
● Null Experiments as Test of Validity
● Spherical Cow
○ When studying any complex system, it is always useful to first eliminate many of the peripheral issues. In other words, do the spherical cow problem first before tackling the super complex version.
● Scale of the Accomplishment
○ Fundamental constants determine the size of things! (h­bar, c, and G)
○ Chart of the Universe
■ Range of Phenomena
● There are 40 powers of 10 between the largest and smallest scaled phenomena. That is truly a fantastic range of human understanding.
■ The chart of the universe looks like it does (straight line) because we have, for
the