Physics – Premed Windsor University School of Medicine and Health Sciences J.C. Rowe Course Instructor.

Pre Med – Physics Chapter 0 - Intro There is more to lectures than the power point slides! Engage your mind - go beyond the class!

PHYICS

What is Physics ? Def’d-1: analysis of nature & how the universe behaves Def’d-2: the scientific study of matter and energy and how they interact with each other Involves: motion, heat, light, electricity, magnetism, atomic structure, gravity etc..

How Does The Natural World Function? Fundamental Questions e.g: How did the universe begin? How will the universe change in the future? How / why does the Sun keep on shining? What are the basic building blocks of matter? How does matter exist?

UNITS (Systéme Internationale) DimensionSI (mks) UnitDefinition Lengthmeters (m)Distance traveled by light in 1/(299,792,458) s Masskilogram (kg)Mass of a specific platinum- iridium allow cylinder kept by Intl. Bureau of Weights and Measures at Sèvres, France Timeseconds (s)9,192,631,700 oscillations of cesium atom

Prefixes In addition to mks units, standard prefixes can be used, e.g., cm, mm,  m, nm

Significant Figures: Division Find the value of 6.49m divided by s Calculator gives ! Too many figures. FALSE Accuracy Only 3 significant figures. Why? 1.27m/s

Number# Significant FiguresRule(s) 48, ,2, (= 4 E-4)11, , ,2,3,4 3,000,000 (= 3 E+6) (= 1.00 E+1)31,3,4

Estimate the number of times a human heart beats during its lifetime. Estimate - a typical heart beats ~60 times per minute: ESTIMATION 2.4 x 10 9 beats/lifetime

Length: DistanceLength (m) Radius of visible universe 1 x To Andromeda Galaxy 2 x To nearest star 4 x Earth to Sun1.5 x Radius of Earth6.4 x 10 6 Sears Tower 4.5 x 10 2 Football field1.0 x 10 2 Tall person 2 x 10 0 Thickness of paper 1 x Wavelength of blue light 4 x Diameter of hydrogen atom 1 x Diameter of proton 1 x

Time: IntervalTime (s) Age of universe 5 x Age of Grand Canyon 3 x years 1 x 10 9 One year3.2 x 10 7 One hour3.6 x 10 3 Light travel from Earth to Moon1.3 x 10 0 One cycle of guitar A string 2 x One cycle of FM radio wave 6 x Lifetime of neutral pi meson 1 x Lifetime of top quark 4 x

Mass: ObjectMass (kg) Milky Way Galaxy 4 x Sun 2 x Earth 6 x Boeing x 10 5 Car 1 x 10 3 Physics Student 7 x 10 1 Dust particle 1 x Top quark 3 x Proton 2 x Electron 9 x Neutrino 1 x

Conversion of Units Example: The Distance from point A to the Andromeda Nebula is 2 x 10 6 light years. What is the distance in km ? 1. Conversion factor: 1 ly = 9.5 x km 2. Insert conversion factor: d = 2 x 10 6 ly & 1 ly = 9.5 x km = 2 x 10 6 x 9.5 x km = 1.9 x km Remember: 10 a x10 b = 10 a+b 10 a / 10 b = 10 a-b

Example: If the speed limit on the German autobahn is 150 kilometers/hour. What is the speed limit in metres/hour ? What is the speed limit in mile/ hour?

Lecture 1, Activity A very good fastball pitcher can throw the ball 100 mi/hr. What is the ball speed in m/s? (Answer in 3 significant figures) m/s m/s m/s 4 – 28.1 m/s m/s correct

Dimensional Analysis Dimension indicates the nature of a physical quantity or the type of unit. Example: Dimension of distance is length : [L] Unit of distance is m, km, miles, … Note: Dimensions of left-hand side and right-hand side of an equation have always to be the same, e.g. when you start with a quantity of dimension length you have to finish with one of dimension length. Powerful check of your computation !

Trigonometry Definition of sine, cosine and tangent: Sin  = opp/hyp Cos  = adj/hyp Tan  = opp/adj Pythagorean Theorem: c 2 = a 2 + b 2

Physics Applied The Lunar Dome Home – designed by the Foster + Partners Company - winners of the European Space Agency design competition