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ENERGY

Science

The 1,2,3s of NRG

Presentation by Andrew Chapman, but conceptual credits go to Gregg Swackhamer and the ASU Modeling Group ☺

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What is the only thing about the universe that never changes?

https://prezi.com/tquii53jgg9z/e-x-v-a-f/

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What is energy?

Energy is the capability to effect change
(ability to make changes)
1^st Law of Thermodynamics: Energy cannot be created or destroyed

But one can store energy
And if one can store it, one can move it
Thus one can transfer it

So, 1 kind of energy (called energy)
2 things to do with it: transfer or store

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Energy Transfer Mechanisms (3)

W

R

Q

∆E

WORKING

(Forces)

RADIATING (distance)

HEATING (contact)

The circle is the “system”
Circle size = amount of energy in the system
Change the circle size (∆E) by transfer of E

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How is energy stored? (Modes)�Kinetic(movement) vs Potential(fields)

Kinetic ∆E_KHow fast?
Thermal ∆E_THHow hot?
Gravitational ∆E_G How high?
Electromagnetic ∆E_EMHow shocking?
Elastic ∆E_ELHow stretched?
Chemical ∆E_CHHow many Calories?
Internal ∆E_INSolid/Liquid/Gas?
Mass ∆E_MHow massive?
… more? (Like E_diss = various NRG transfers due to friction effects)

This slide can be confusing to some - take some time to discuss how these are just storage modes, not different “kinds” of energy (there’s only one kind!)

It helps to think in terms of scale – Ek = large bodies, Eth = momentum of molecules (This is a good time to talk about friction – how it changes motion of large bodies into greater vibrations of molecules (heat). The field effects of Eg and Eem also differ in scale (and probably mechanism too, but since we’re not too sure about how these fields actually work we can’t be too confident here!) Elastic is how larger objects/molecules are stretched, while Ech can be though of in terms of how molecules are connected (stretched), the rings of sugar from photosynthesis are a good discussion example. Einternal is the organization of the particles (solid vs liquid vs. gas).though, reading Swackhamer’s paper and other similar materials about making energy coherent is REALLY helpful! It may help the students to categorize them as potential (G, EL, CH, IN, EM) and kinetic (K, Th) or arrangements versus relative motion…

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The 1, 2, 3s of eNeRGy

W

R

Q

∆E

WORKING

(Forces)

RADIATING (distance)

HEATING

(contact)

1 kind of energy (called energy)

2 things you can do to energy (transfer & store)

∆E_KKinetic

∆E_THThermal

∆E_ELElastic

∆E_CHChemical

∆E_G Gravitational

∆E_EMElectromagnetic

∆E_INInternal

∆E_Mmass

LOTS OF WAYS

TO STORE NRG

3 WAYS TO TRANSFER NRG

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Changing how energy is stored in a system

∆E = ∆W + ∆R + ∆Q
Pie charts (circles) show amount of E in a system
And how it is stored
Can you describe the situation below?

E_g

Eg

W

Eg Ek

W

R

Q

∆E

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Changing how energy is stored in a system

∆E = ∆W + ∆R + ∆Q
LOL diagrams (bar charts) can show amount of E in a system
And how it is stored
Can you describe the situation below?

W

R

Q

∆E

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Examples of NRG storage and transfer

Demo (burning nuts) (quemando nueces)
Photosynthesis (Elodea)
Lighting a match
Buggies
Lifting weights
Playing with a windup toy
Melting Ice (and more?)
Burning a candle
Eating

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Describe the energy storage and transfer(s) in a system during a change

What is the system?

Describe “BEFORE” Describe “AFTER”

Does the energy of the system increase/decrease/not change?

If so, which of W,Q,R are involved?

Now draw LOL chart(s) to show what you described

(Label E_k, E_g, E_el, E_th, E_ch, E_int, E_em)

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Describe the energy storage and transfer(s) in a system during a change

What is the system?

Describe “BEFORE” Describe “AFTER”

Does the energy of the system increase/decrease/not change?

If so, which of W,Q,R are involved?

Now draw pie/LOL chart(s) to show what you described

(Label E_k, E_g, E_el, E_th, E_ch, E_int, E_em)

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Link to interactive whiteboards

https://puhsd210-my.sharepoint.com/:p:/g/personal/achapman1_phoenixunion_org/EYg2oIAMUvFOrb4m-ppTCg4BXPMHkLJivBccIQ4k70hCpA?e=UNia8C

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E

x

v

a

F

Δ

E

x

v

a

F

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The 1, 2, 3s of eNeRGy

W

R

Q

∆E

WORKING

(Forces)

RADIATING (distance)

HEATING

(contact)

1 kind of energy (called energy)

2 things you can do to energy (transfer & store)

∆E_KKinetic

∆E_THThermal

∆E_ELElastic

∆E_CHChemical

∆E_G Gravitational

∆E_EMElectromagnetic

∆E_INInternal

∆E_Mmass

LOTS OF WAYS

TO STORE NRG

3 WAYS TO TRANSFER NRG