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Deletions are marked like this. Additions are marked like this.
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||<:30%>[:PiraScheme#Thermodynamics: Table of Thermodynamics Demonstration]||<:30%>[:TDEquipmentList: Thermodynamics Equipment List]||<:30%>[:Demonstrations:Lecture Demonstrations]||
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'''Topic and Concept:'''
  Thermal Properties of Matter, [:ThermalProperties#Thermometry: 4A30. Thermometry]
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 * '''Cabinet:''' Thermodynamics Cabinet
 * '''Bay:''' (A3)		  * '''Cabinet:''' [:ThermoCabinet:Thermodynamics (TD)]
 * '''Bay:''' [:ThermoCabinetBayA3:(A3)]
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(attachment photo showing the fully set up demonstration) attachment:photo
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'''Description:''' '''Abstract:'''
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This can also be called expansion rods. This can also be called expansion rods. A metal blue box with various rods of different materials.
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||Metal||[:ThermoCabinetBayA3: TD, A3, Shelf #1]|| ||
||all other parts||ME, Bay B1, Shelf #2|| ||
||...||ME, Bay B1, Shelf #2|| ||
||Possible supplies that are needed||Rode and Tack Cabinet|| ||
||...|| In Lecture Halls|| ||
||...|| Stock Cabinet || ||
||...|| Stock Cabinet || ||		 ||Metal blue box with rods||[:ThermoCabinetBayA3: TD, A3, Shelf #1]||<:>4A30.58 ||
||Safety glove and glasses|| || ||
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'''Setup:'''
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 1. Make a Setup check list.
 1. ...		 '''''Important Setup Notes:'''''
 * This demonstration requires a supply of methane gas usually provided by the [:RedWhiteGasCarts: red and white gas carts] found in rooms 2103, 2241, (and 2223 upon request).


'''Setup and Procedure:'''
 1. Choose a rod and place it on the holder.
 1. Connect the burner to the methane supply.
 1. Open the valve to let the gas flow, and light the burner using a match or lighter.
 1. Place the flame under the rod to heat it.
 1. Note the rate of expansion.
 1. Turn of the gas by closing the valve, and allow some time for the rod to cool.
 1. Carefully (using insulated gloves) switch out this rod for another one and repeat the heating process.
 1. Note that the rate of expansion for this different material is different from the first rod.

 
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 1. List any Warnings....
 1. Demonstration may require practice.		  * Beware of the heated rods - they can cause serious burns!
 * Wear the safety grove and glasses.
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'''Demonstration:'''
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Insert description of demonstration, how is the demonstration preformed. '''Discussion:'''
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||attachment other photos||attachment other photos||
||attachment other photos||attachment other photos||		 A given material of given length (1D), area (2D), or volume (3D) will have different geometric size at different temperatures. The equations describing this behavior is

 ΔL/L = α,,L,,*ΔT (1D)

 ΔA/A = α,,A,,*ΔT = α,,L,,^2^*ΔT (2D)

 ΔV/V = α,,V,,*ΔT = α,,L,,^3^*ΔT (3D)

where L, A, and V are the initial length, area, and volume respectively when the material has temperature T,,i,,. The Δ denotes the change in that quantity (final - initial). α,,L,,, α,,A,,, α,,V,, are the linear, area, and volumetric coefficients of thermal expansion respectively. Note that for the 2D and 3D cases, equating α,,A,, to α,,L,,^2^ and α,,V,, to α,,L,,^3^ is only valid for small expansions (or contractions) in isotropic materials.

This demonstration shows that different materials have different coefficients of thermal expansion. We have five different material rods of equal length that start at room temperature and can be heated to the temperature of the flame. Thus, ΔT is the same for all the rods For one rod, you will see (using the scale) that ΔL increases at some rate during heating. When another rod is heated, its ΔL increases at a different rate. To show this difference most dramatically, compare the rate of increase of ΔL between kovar (our smallest α,,L,,) and brass (our largest α,,L,,).

Our available materials with their respective linear thermal expansion coefficients in ascending order
||'''Material'''||'''α,,L,, (x 10^-6^ K^-1^)'''||
||Kovar|| 5.5 ||
||Titanium|| 8.6 ||
||Cold-rolled steel|| 12.4 ||
||Nickle|| 13.0 ||
||Brass|| 18.7 ||

 
||attachment:photos||attachment:photos||attachment:photos||attachment:photos||


'''Videos:'''
 * [https://www.youtube.com/user/LectureDemostrations/videos?view=1 Lecture Demonstration's Youtube Channel]
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 1. List any references

[Insert a back link to main topic list]

[:Demonstrations:Demonstrations]		  * [https://en.wikipedia.org/wiki/Thermal_expansion Wikipedia - Thermal Expansion]
 * [http://en.wikipedia.org/wiki/Coefficient_of_thermal_expansion Wikipedia - Coefficient of Thermal Expansion]

[:PiraScheme#Thermodynamics: Table of Thermodynamics Demonstration]

[:TDEquipmentList: Thermodynamics Equipment List]

[:Demonstrations:Lecture Demonstrations]

Thermal Expansion of Metal Rods , 4A30.58

Topic and Concept:

Location:

attachment:photo

Abstract:

This can also be called expansion rods. A metal blue box with various rods of different materials.

Equipment

Location

ID Number

Metal blue box with rods

[:ThermoCabinetBayA3: TD, A3, Shelf #1]

4A30.58

Safety glove and glasses

Important Setup Notes:

  • This demonstration requires a supply of methane gas usually provided by the [:RedWhiteGasCarts: red and white gas carts] found in rooms 2103, 2241, (and 2223 upon request).

Setup and Procedure:

  1. Choose a rod and place it on the holder.
  2. Connect the burner to the methane supply.
  3. Open the valve to let the gas flow, and light the burner using a match or lighter.
  4. Place the flame under the rod to heat it.
  5. Note the rate of expansion.
  6. Turn of the gas by closing the valve, and allow some time for the rod to cool.
  7. Carefully (using insulated gloves) switch out this rod for another one and repeat the heating process.
  8. Note that the rate of expansion for this different material is different from the first rod.

Cautions, Warnings, or Safety Concerns:

  • Beware of the heated rods - they can cause serious burns!
  • Wear the safety grove and glasses.

Discussion:

A given material of given length (1D), area (2D), or volume (3D) will have different geometric size at different temperatures. The equations describing this behavior is

  • ΔL/L = αL*ΔT (1D)

    ΔA/A = αA*ΔT = αL2*ΔT (2D)

    ΔV/V = αV*ΔT = αL3*ΔT (3D)

where L, A, and V are the initial length, area, and volume respectively when the material has temperature Ti. The Δ denotes the change in that quantity (final - initial). αL, αA, αV are the linear, area, and volumetric coefficients of thermal expansion respectively. Note that for the 2D and 3D cases, equating αA to αL2 and αV to αL3 is only valid for small expansions (or contractions) in isotropic materials.

This demonstration shows that different materials have different coefficients of thermal expansion. We have five different material rods of equal length that start at room temperature and can be heated to the temperature of the flame. Thus, ΔT is the same for all the rods For one rod, you will see (using the scale) that ΔL increases at some rate during heating. When another rod is heated, its ΔL increases at a different rate. To show this difference most dramatically, compare the rate of increase of ΔL between kovar (our smallest αL) and brass (our largest αL).

Our available materials with their respective linear thermal expansion coefficients in ascending order

Material

αL (x 10-6 K-1)

Kovar

5.5

Titanium

8.6

Cold-rolled steel

12.4

Nickle

13.0

Brass

18.7

attachment:photos

attachment:photos

attachment:photos

attachment:photos

Videos:

References:

[:Instructional:Home]

fw: MetalRods (last edited 2021-02-09 17:31:36 by srnarf)