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| ||<30% style="text-align:center">[[PiraScheme#Thermodynamics|Table of Thermodynamics Demonstration]] ||<30% style="text-align:center">[[TDEquipmentList|Thermodynamics Equipment List]] ||<30% style="text-align:center">[[Demonstrations|Lecture Demonstrations]] || | ||<30% style=""text-align:center" ">[[PiraScheme#Thermodynamics|Table of Thermodynamics Demonstration]] ||<30% style=""text-align:center" ">[[TDEquipmentList|Thermodynamics Equipment List]] ||<30% style=""text-align:center" ">[[Demonstrations|Lecture Demonstrations]] || |
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'''pira200 Listed''' |
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| ||<40% style="text-align:center">'''Equipment''' ||<30% style="text-align:center">'''Location''' ||<25% style="text-align:center">'''ID Number''' || | ||<40% style=""text-align:center" ">'''Equipment''' ||<30% style=""text-align:center" ">'''Location''' ||<25% style=""text-align:center" ">'''ID Number''' || |
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| ||A ring with stand and a ball with hanger ||[[ThermoCabinetBayA3|TD, A3, Shelf #1]] ||<style="text-align:center">4A30.20 || ||Burner with an iron ring tripod and wire net screen ||location ||<style="text-align:center">NA || ||An iron ring tripod and a screen ||location ||<style="text-align:center">NA || ||Safety grove and glasses ||location ||<style="text-align:center">NA || |
||A ring with stand and a ball with hanger ||[[ThermoCabinetBayA3|TD, A3, Shelf #1]] ||<style=""text-align:center"">4A30.20 || ||Burner with an iron ring tripod and wire net screen ||location ||<style=""text-align:center"">NA || ||An iron ring tripod and a screen ||location ||<style=""text-align:center"">NA || ||Safety grove and glasses ||location ||<style=""text-align:center"">NA || |
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| When the ball is heated, its dimensions increase while maintaining their relative proportions. Heating causes the molecular bonds to lengthen, which causes the material to expand. This is considered a 2D expansion since the quantity of importance for the ball to fit through the ring is the cross sectional area. The expansion can be described by ΔA/A = α,,A,,*ΔT = α,,L,,^2^*ΔT where A is the area at temperature T,,i,,, ΔA is the change in area when the material is at temperature T,,f,,, ΔT is T,,f,, - T,,i,,, and α is the coefficient of thermal expansion which depends on the material. See references below for more information. |
When the ball is heated, its dimensions increase while maintaining their relative proportions. Heating causes the molecular bonds to lengthen, which causes the material to expand. This is considered a 2D expansion since the quantity of importance for the ball to fit through the ring is the cross sectional area. The expansion can be described by ΔA/A = α,,A,,*ΔT = α,,L,,^2^*ΔT where A is the area at temperature T,,i,,, ΔA is the change in area when the material is at temperature T,,f,,, ΔT is T,,f,, - T,,i,,, and α is the coefficient of thermal expansion which depends on the material. See references below for more information. |
Large Ball and Ring Stand, 4A30.20
Topic and Concept:
Thermal Properties of Matter, 4A30. Solid Expansion
pira200 Listed
Location:
Cabinet: Thermodynamics Cabinet
Bay: (A3)?
Shelf: #1?
Description:
This demonstration has a ball and ring with stand. It demonstrates the thermal expansion of the material by heating the ball.
Equipment |
Location |
ID Number |
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A ring with stand and a ball with hanger |
4A30.20 |
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Burner with an iron ring tripod and wire net screen |
location |
NA |
An iron ring tripod and a screen |
location |
NA |
Safety grove and glasses |
location |
NA |
Rooms 2103, 2241, (and 2223 upon request) |
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Important Setup Notes:
This demonstration requires a supply of methane gas usually provided by the red and white gas carts found in rooms 2103, 2241, (and 2223 upon request).
Setup and Procedure:
To light the burner, connect the attached gas hose to the gas out (red panel) on the red and white gas cart.
- Open the gas valve.
- Light a match and bring it near the top of the burner.
- The flame will ignite the gas. Adjust the flame height accordingly by adjusting the valve.
- Show that the ball can get through the ring.
- Put the lit burner beneath the tall ring stand with the screen on the top.
- Lower the ball onto the screen using the attached hook. It will take about a minute for the ball to heat up enough to not fit through the ring
- Take the ball off the stand and try to lower the ball through the ring.
If the ball fits through the ring, repeat steps 7 & 8. Otherwise, let the ball rest on the ring. As it cools, it will eventually shrink enough to drop through the ring.
Cautions, Warnings, or Safety Concerns:
- Always use the gloves and safety glasses throughout this demonstration.
- Beware of the heated plate - contact with skin could cause severe burns!
Discussion:
When the ball is heated, its dimensions increase while maintaining their relative proportions. Heating causes the molecular bonds to lengthen, which causes the material to expand. This is considered a 2D expansion since the quantity of importance for the ball to fit through the ring is the cross sectional area. The expansion can be described by ΔA/A = αA*ΔT = αL2*ΔT where A is the area at temperature Ti, ΔA is the change in area when the material is at temperature Tf, ΔT is Tf - Ti, and α is the coefficient of thermal expansion which depends on the material. See references below for more information.
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Videos:
References: