Differences between revisions 17 and 18

Large Ball and Ring Stand, 4A30.20

Topic and Concept:

Thermal Properties of Matter, 4A30. Solid Expansion

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

A ring with stand and a ball with hanger	TD, A3, Shelf #1	4A30.20
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
Red and white gas carts	Rooms 2103, 2241, (and 2223 upon request)

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 = α_A*ΔT = α_L²*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.

Videos:

Lecture Demonstration's Youtube Channel

References:

Home

-  ⇤ ← Revision 17 as of 2013-07-17 18:41:43 → 
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  Editor: srnarf
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+   ← Revision 18 as of 2013-07-17 18:53:51 → ⇥
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  Editor: srnarf
  Comment:
-Deletions are marked like this.
+Additions are marked like this.
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-=  Large Ball and Ring Stand, 4A30.20 =
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+= Large Ball and Ring Stand, 4A30.20 =
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-  Thermal Properties of Matter, [[ThermalProperties#SolidExpansion|4A30. Solid Expansion]]
+ . Thermal Properties of Matter, [[ThermalProperties#SolidExpansion|4A30. Solid Expansion]]
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-This demonstration has a ball and ring with stand. It demonstrates the thermal expansion of the material by heating the ball.
+This demonstration has a ball and ring with stand. It demonstrates the thermal expansion of the material by heating the ball.
||<40%  style="text-align:center">'''Equipment''' ||<30%  style="text-align:center">'''Location''' ||<25%  style="text-align:center">'''ID Number''' ||
|| || || ||
||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 ||
||[[RedWhiteGasCart|Red and white gas carts]] ||Rooms 2103, 2241, (and 2223 upon request) || ||
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+Line 29:
-||<:style="width: 60%" :40%>'''Equipment'''||<:30%>'''Location'''||<:25%>'''ID Number'''||
|| || || ||
||A ring with stand and a ball with hanger||[[ThermoCabinetBayA3| TD, A3, Shelf #1]]||<:> 4A30.20 ||
||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 ||
||[[RedWhiteGasCart|Red and white gas carts]] ||Rooms 2103, 2241, (and 2223 upon request) || ||
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 '''Setup and Procedure:'''
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+Line 43:
-. Heat the ball by the burner. It may take a lot of time, so just put it on the iron ring tripod and heat it.
 1. Then Put the ball over the ring. This time the ball should cannot get through the ring.
+. Put the lit  burner beneath the tall ring stand with the screen on the top.
 1. 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
 1. Take the ball off the stand and try to lower the ball through the ring.
 1. 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.
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+Line 49:
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+Line 53:
+'''Discussion:'''
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-'''Discussion:''' 

This demonstration show the thermal expansion property of the material which is the tendency of matter to change volume corresponding to the temperature changes.
+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.
|| {{attachment:4A30-20_01a.jpg}} || {{attachment:4A30-20_02a.jpg}} || {{attachment:BallStand03-250.jpg}} || {{attachment:BallStand04-250.jpg}} ||
|| {{attachment:BallStand05-250.jpg}} || {{attachment:BallStand06-250.jpg}} ||
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-||{{attachment:4A30-20_01a.jpg}}||{{attachment:4A30-20_02a.jpg}}||{{attachment:BallStand03-250.jpg}}||{{attachment:BallStand04-250.jpg}}||
||{{attachment:BallStand05-250.jpg}}||{{attachment:BallStand06-250.jpg}}||
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fw: Diff for "LBRS"

Large Ball and Ring Stand, 4A30.20