OCTOBER STARS MEETING

BRIEF INTRODUCTION

HIGGS BOSON PRESENTATION & DISCUSSION

FIRST SECTION OF ‘THE THERMODYNAMICS OF EVERYDAY LIFE’ ~ Introduction & Scope

ASTRONOMY DISCUSSION

AOB

THE THERMODYNAMICS OF EVERYDAY LIFE

STARS Seminar/Symposium 1

An amble through some interesting aspects of science and technology

John Pearce

INTRODUCTION AND SCOPE

• Index & Contents

• Areas Covered

• Top Level Definitions

• Hooks & Links

INDEX AND CONTENTS 1The Thermodynamics of Everyday Life

1. INTRODUCTION AND SCOPEIndex & contents, Areas covered, Top level definitions, Hooks & links2. FUNDAMENTALS 1More detailed definitions, Energy work & power etc, Some laws, Some mathematics3. FUNDAMENTALS 2Elements, Chemistry, Atomic structure, Quanta, Some more mathematics 4. BURNING QUESTIONSFuels, Combustion, Some more chemistry, Nuclear reactions5. ITS NEARLY ALL SUNSHINEStars nova & supernova, Stellar processes, Photosynthesis, Wind & water, Tides &

geothermal.6. ALL CHANGE – CLIMATE & WEATHERClimate & weather as a heat engine, Greenhouse effect, Goldilocks planet

INDEX AND CONTENTS 2The Thermodynamics of Everyday Life

7. ITS LIFE – BUT NOT AS WE KNOW ITFlora & fauna, Aerobic & anaerobic, More photosynthesis, Carbohydrates,

Atmosphere8. GETTING ABOUT – PRIME MOVERS & HEAT ENGINESWaterwheels & windmills, Atmospheric & steam Engines, Internal

combustion engines, Guns scale & energy density, Transport9. KEEPING OUT THE COLD – THE OLD BOILERHeating & insulation, Refrigeration & heat pumps, Solar & the future10. GROWING AND MAKING THINGSAgricultural revolution, Energy content & accounting, Sustainability11. IT’S DOWNHILL ALL THE WAYCosmology, Entropy & heat death, Information as energy, Fate of the solar

system12. SUMMARY – CONCLUSIONS - FUTURE

AREAS COVERED 1

• Simple Physics – Heat, Light & Sound• Mechanics• Dynamics –

– Aerodynamics– Hydrodynamics (Fluid dynamics)– Thermodynamics

• Chemistry• Atomic Physics –

– Atomic Structure– Nuclear Physics– Quantum Physics

AREAS COVERED 2

• Astrophysics & Cosmology

• Evolution

• Optics

• Electronics/Electricity/Magnetism ~ Electromagnetics

• Mathematics –– General Concepts of relevance

– Simple Harmonic Motion

– Some Systems Aspects

– Modelling & Simulation

Top Level Definitions 1

• Simple Physics – Heat, Light & Sound.• Mechanics – Forces & Motion ; Statics &

Dynamics.• Dynamics – Primarily concerned with Motion.

– Hydrodynamics – the movement of water or, more generally the movement of fluids (Fluid dynamics)

– Aerodynamics – the movement of air or, more generally the movement of gases

– Thermodynamics – the movement of heat

• Chemistry.

Top Level Definitions 2

• Atomic Physics – the Structure & Workings of the Atom.– Atomic Structure– Nuclear Physics– Quantum Physics

• Astrophysics & Cosmology• Evolution• Optics – the understanding and use of light• Electronics/Electricity/Magnetism

Top Level Definitions 3

• Mathematics– General Concepts of Relevance

• Accounting, Continuity, Conservation, Conversion, Efficiency, Robustness & Resilience, Growth Curves, Minimum Action, Occam’s Razor, Pareto Principle, Dimensions & Dimensional Analysis, Scale Effects.

– Simple Harmonic Motion• Pendulums, Oscillations, Waves, Resonance,

Damping, Coupling of Resonators, Bio rhythms.

Top Level Definitions 4

• Mathematics– Some Systems Aspects

• Systems, States, Boundaries, Domains, Time Constants, Algorithms.

– Modelling & Simulation• Relationships, Complex Models, Simulations,

Analogues, Complexity.

HOOKS AND LINKS

• A table of areas covered against the names of major contributors– Look them up on Google to find out more

• A table of areas covered against sections of the presentation– Maps the science onto the subject

• A table of the mathematical aspects against the areas covered– Maps the mathematics onto the science

HOOKS AND LINKS ~ TABLE 1

HOOKS AND LINKS ~ TABLE 2

HOOKS AND LINKS ~ TABLE 3

• Handout

HOOKS AND LINKSHONEY

WHAT IS HONEY?

• A FLUID

• A FOOD

• A FUEL

• MADE BY BEES

• MADE FROM NECTAR AND POLLEN

A FLUID

• A Common state of matter.

– Fills Container

– Forms a Free Surface

• Hydrodynamics/Fluid Dynamics/Fluid Mechanics

– Highly Viscous ~ Simple Experiments

– Fluid Flow ~ Laminar ~ Turbulent ~ Bee & Aerodynamics

– Scale Effects ~ Bee & Size

A FOOD

• EATEN BY BEES (AND ANY ANIMAL THAT CAN GET IT)

• DESIRABLE TASTE ~ SWEET

• A MIXTURE OF SUGARS ~ CARBOHYDRATES– Chemically ~ CKH2NON ~ For sucrose K=12 & N=11

– Can be fermented into honey based drinks ~ Methyglyn~ Mead

– Fermented by yeasts into alcohol, chemically ~ C2H5OH

A FUEL

• CARBOHYDRATES/SUGARS MAKE GOOD FUELS– A fuel is something that can be burnt to produce lots of heat. We

will do some experiments to burn sugar at a later meeting.– We burn cellulose in wood and cellulose is a chain of sugars.

Interestingly, cellulose is also a very good structural material ~ more of that at a later meeting.

– Bees and animals metabolise carbohydrates/sugars as fuels.

• ALCOHOLS (Partially ‘burnt’ sugars) MAKE GOOD FUELS– We will do some experiments to burn alcohol at a later meeting.

Many of us will be doing this ourselves before then, but we don’t burn alcohol very well, although we enjoy trying.

BEE

WHAT IS A BEE?

• A FLYING INSECT– Bees & aerodynamics

– Bees & insects & size

• BEE COLONIES AND SWARMS– Bee communication

– Bee parasites

– Bee populations

BEES AND AERODYNAMICS

• Aerodynamic theory says bees cannot fly– Not quite true ~ Bees the size of people cannot fly ~ bees the size

of bees can ~ it’s all to do with viscosity and Reynolds Number.

– Reynolds Number is a non dimensional scale factor which relates inertial forces to viscous forces ~ we measured it with the knife experiment earlier.

– Its named after Osborne Reynolds and is :- size x speed x density all divided by viscosity.

BEES AND INSECTS AND SIZE

• Besides aerodynamics, other scale effects also impact on the size of bees and insects.– Bees and insects have exo skeletons made of chitin ~ if they get too big

their bodies cannot support them.

– A more dominant scale effect is how bees and insects absorb oxygen from the air (needed to burn the honey). They absorb oxygen through channels in their skeleton and the rate of exchange is limited not only by area, but by diffusion of the gases through the channels.

Gills used by fish are better since water (containing oxygen) is pushed past them, either by pumping or by their forward movement. Lungs are even better since air (with more available oxygen) is pumped into them by breathing. That’s why the biggest creatures in the sea are not fish but air breathing mammals.

BEE COMMUNICATION

• Bees perform a ‘dance’ to tell other bees where sources of nectar and pollen are.– This might be thought of as a primitive form of

language.

– This is a link you might like to explore.

BEE PARASITES

• Bees can be attacked by a parasitic tic ~ Varroa mite, both as larvae and adult bees.

• Wax moth larvae eat the wax honeycomb.

BEE POPULATIONS

• Parasites and diseases could be contributing to collapsing bee populations.

• Pollutants and changing weather patterns are also thought to be contributing factors.

• However, population levels tend to be mathematically chaotic ~ XN+1 =RX N(1-X N) (normalised to 1)

• So how do we determine which effects are dominant?

• And how do we determine which are the dominant effects within the effects?