experimental physics ep1 mechanics - introduction · bußtag & bettag 21.11.2018 (mittwoch)...
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Experimental Physics - Mechanics - Introduction 1
Experimental Physics
EP1 MECHANICS
- Introduction -
Rustem Valiullin
http://uni-leipzig.de/~valiu/
Experimental Physics - Mechanics - Introduction 2
Lecturer: Rustem Valiullin
#508, Tel. 341 97 32 515
Teaching assistants: [email protected]
Demonstrations: Axel Märcker
Ulrich Kemper
Saurabh Raj
Tobias Splith
Experimental Physics - Mechanics - Introduction 3
Overall: ~29 lectures, ~13 seminars
Wintersemester 2018/19
Zeitraum vom 01.10.2018 bis 31.03.2019
Einführungswoche vom 08.10.2018 bis 12.10.2018
Lehrveranstaltungen vom 15.10.2018 (Montag) bis 09.02.2019 (Samstag)
Immatrikulationsfeier 17.10.2018 (Mittwoch) während der Feier keine
Lehrveranstaltungen, anyway no seminar
Reformationstag 31.10.2018 (Mittwoch) vorlesungsfrei
Bußtag & Bettag 21.11.2018 (Mittwoch) vorlesungsfrei
dies academicus 03.12.2018 (Montag) Projekttag
Jahreswechsel vom 24.12.2018 bis 06.01.2019 vorlesungsfrei
Tag der offenen Tür 10.01.2019 (Donnerstag)
On 19th of October, this Friday, there will be a written test on mathematics and physics.
Experimental Physics - Mechanics - Introduction 4
Experimental Physics - Mechanics - Introduction 5
Experimental Physics - Mechanics - Introduction 6
Content
1. Motion along a line
2. Vectors and scalars
3. Motion in three dimensions
4. Laws of motion 1, 2
5. Work and energy
6. Potential energy
7. System of particles
8. Collisions
9. Rotations 1, 2
10. Static equilibrium
11. Gravity 1, 2
12. Rotational motion
13. Elasticity
14. Fluid mechanics 1, 2
15. Oscillations
16. Forced oscillations
17. Damped and driven oscillations
18. Power spectrum, coupled oscillator
19. Waves
20. Sound waves
21. Temperature
22. Kinetic theory 1, 2
Experimental Physics - Mechanics - Introduction 7
Bibliography
Fundamentals of Physics 8th edition D. Halliday, R. Resnick, J. Walker
Kompaktkurs Physik
H. Pfeifer, H. Schmiedel, R. Stannarius
On your choice
Any Author, Many Authors
Experimental Physics - Mechanics - Introduction 8
Physics
fusis – nature, natural thing
Observation
Experimentation
Hypothesis
Theory
Prediction
Experimentation
Refinement
Experimental Physics - Mechanics - Introduction 9
Liters to Milliliters Liters to Gallons Liters to Ounces Liters to Centiliters Liters to Cups Liters to Pints Liters to Cubic Meters Liters to Cubic Feet Liters to Barrels Liters to Tablespoons Liters to Teaspoons Liters to Cubic Inches Liters to Cubic Centimeters Liters to Microliter Liters to Quarts Liters to Cubic Yards Liters to US Barrels (Dry) Liters to US Barrels (Liquid) Liters to US Barrels (Oil) Liters to US Barrels (Federal) Liters to UK Barrels Liters to US Gallons (Liquid) Liters to US Gallons (Dry) Liters to UK Gallons Liters to US Quarts (Liquid) Liters to US Quarts (Dry) Liters to UK Quarts Liters to US Pints (Liquid) Liters to US Pints (Dry) Liters to UK Pints Liters to US Cups Liters to Canadian Cups Liters to Metric Cups Liters to US Gills Liters to US Tablespoons Liters to UK Tablespoons Liters to Metric Tablespoons Liters to US Teaspoons Liters to UK Teaspoons Liters to Metric Teaspoons Liters to US Fluid Ounces Liters to UK Fluid Ounces Liters to Cubic Millimeters Liters to Kiloliters Liters to Gills (UK)
Meters to Kilometers Meters to Millimeters Meters to Miles Meters to Feet Meters to Inches Meters to Centimeters Meters to Yards Meters to Micron Meters to Parsecs Meters to Lightyears Meters to Decimeters Meters to UK Nautical Miles Meters to Microinches Meters to US Nautical Miles Meters to Nautical Miles Meters to Furlongs Meters to Chains Meters to US Leagues Meters to Nautical Leagues Meters to UK Leagues Meters to UK Nautical Leagues
Kilograms to Grams Kilograms to Pounds Kilograms to Ounces Kilograms to Milligrams Kilograms to Stones Kilograms to Ton Kilograms to Carats Kilograms to Micrograms Kilograms to Troy Pounds Kilograms to Troy Ounces Kilograms to Grains Kilograms to Tonnes Kilograms to Hundredweights Kilograms to Metric Tons (or Tonnes) Kilograms to Long Tons (UK) Kilograms to Short Tons (US) Kilograms to Short Hundredweights (US) Kilograms to Long Hundredweight
http://www.metric-conversions.org/
The weight of an elephant, sometimes more specifically "the weight of an African bull elephant" (about 6 tons), is sometimes used by paleontologists as a unit of weight when describing the weight of large dinosaurs.
A unit of volume used in Australia for water. One Sydney Harbour, also called a Sydharb (or sydarb), is the amount of water in Sydney Harbour: approximately 500 gigalitres (about 400,000 acre-feet)
Experimental Physics - Mechanics - Introduction 10
Basic measure units
Name Symbol Measure
meter m length
kilogram kg mass
second s time
Ampere A electric current
Kelvin K thermodynamic temperature
mole mol amount of substance
candela cd luminous intensity
Experimental Physics - Mechanics - Introduction 11
Three basic measure units - meter
Since 1983: The meter is the length of the path travelled by light
in vacuum during a time interval of 1/299 792 458 of a second.
http://physics.nist.gov/cuu/Units/meter.html
- the length of a pendulum having a half-period of one second
1791 one ten-millionth of the length of the meridian through Paris from pole to the equator
1889 prototype made of an alloy of platinum with 10 percent iridium and to be measured at the melting point of ice
1927 the distance, at 0°, between the axes of the two central lines marked on the bar of platinum-iridium kept at the BIPM (institute of standards)
1960 based upon a wavelength of krypton-86 radiation
Experimental Physics - Mechanics - Introduction 12
Experimental Physics - Mechanics - Introduction 13
8 µm
Experimental Physics - Mechanics - Introduction 14
Three basic measure units - second
? was defined originally as the fraction 1/86 400 of the mean solar day
1960 definition based on the tropical year
Since 1967: The second is the duration of 9 192 631 770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom.
http://physics.nist.gov/cuu/Units/meter.html 24 hours 60 minutes 60 second = 86400
Experimental Physics - Mechanics - Introduction 15
Experimental Physics - Mechanics - Introduction 16
Three basic measure units - kilogram
18th
century
the mass of a cubic decimeter of water
1889 the international prototype of the kilogram, made of
platinum-iridium
Since 1901: The kilogram is the unit of mass;
it is equal to the mass of the international
prototype of the kilogram.
http://physics.nist.gov/cuu/Units/meter.html
Avogadro project
Experimental Physics - Mechanics - Introduction 17
Experimental Physics - Mechanics - Introduction 18
Dimensional analysis
Density V
m
Length - L Mass - M Time - T
Velocity
3L
M
t
x
T
L
mntx nmnm
n
mn TLTT
LLt
n=1 m=1 11tx
Experimental Physics - Mechanics - Introduction 19
Estimates and orders of magnitude
Estimate the area covered by the total population of penguins in Antarctica.
~ 50 million penguins
0.5 m
0.5 m
14,000,000 km2
3.1415926535897932384626433832795
Experimental Physics - Mechanics - Introduction 20
Measurements error
rx - real value of a (non-quantized) physical value
ix - measured value of the physical value
ri xx - absolute error
r
ri
x
xx - relative error
Experimental Physics - Mechanics - Introduction 21
Average value
x - typically denotes an ensemble averaged value
N
i
ixN
x1
1With increasing number N of trials, <x> will tend to xr!
-20 0 20
0.00
0.02
0.04
0.06
0.08
p(x
)
x
Experimental Physics - Mechanics - Introduction 22
Gaussian or error function, normal distribution
p(x)dx – probability that a measured quantity lies between x and x+dx
2
2
2 2
)(exp
2
1)(
rxxxp
22 )()(
)(
1)(
dxxpxx
xdxxxp
dxxp
r
r
– standard deviation
2 – variance, mean square deviation
0 20 40 60 80 100
0.00
0.02
0.04
0.06
0.08
p(x
)
x
Experimental Physics - Mechanics - Introduction 23
Uncertainty
r
r
x
x
dxxpP )()(
2 xxwith 95% confidence
xr
xxwith 68% confidence
Experimental Physics - Mechanics - Introduction 24
Uncertainty of the mean
N
i
ixN
x1
1
𝜎 =1
𝑁 − 1 𝑥𝑖 − 𝑥
2
𝑁
𝑖=1
𝑢 =𝜎
𝑁=
1
𝑁(𝑁 − 1) 𝑥𝑖 − 𝑥
2
𝑁
𝑖=1
Mean value
Standard deviation
Standard deviation
of the mean
Experimental Physics - Mechanics - Introduction 25
The International System of Units (SI). It is a good
custom to provide anything in the SI units.
Always check yourself for a proper dimension.
It might be very helpful to check the
order-of-magnitude value.
Errors are important! Do not forget
to report on the uncertainty and
to round the values.
To remember!