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--- demonstrations:4_thermodynamics:4b_heat_and_the_first_law:nail_burner:start [2019/02/14 23:33] – external edit 127.0.0.1
+++ demonstrations:4_thermodynamics:4b_heat_and_the_first_law:nail_burner:start [2020/02/03 20:48] (current) – demoroom
@@ Line 1: / Line 1: @@
 ====== Nail Burner ======
-{{tag>nail transformer variac needs_review untagged unlocated}}
+{{tag> thermodynamics transformer variac AC blackbody_radiation joule_heating weins_law located}}
 <WRAP box right>
@@ Line 11: / Line 11: @@
 ===== Description =====
-A demonstration using the concept of Joule heating to show Wein's Law and the AC concept of a step-down transformer.     Classes Used: PHYS 100, PHYS 153, ASTR 101, ASTR 201
+The demonstration consists of a step-down transformer with a fixture to attach a nail in series, mounted on a metal base with a power indicator light and a fuse.
-Blackbody radiation, transformer (AC), Wein's law
 ===== Purpose =====
+This demonstrates the operation of a step-down transformer in a dramatic manner, by using a transformer to step up the current enough that it'll melt a steel nail via Joule heating. This can also be used to show Wein's law, in conjunction with the [[demonstrations:9_equipment:infrared_camera:start|Infrared camera.]]
-A demonstration using the concept of Joule heating to show Wein's Law and the AC concept of a step-down transformer.
 ===== Apparatus =====
+  * Nail burning apparatus
-Nail burning apparatus, nails, leather gloves, eye protection
+  * Nails
+  * Leather gloves and eye protection
+  * [[demonstrations:9_equipment:variac:start|Variac]] (Optional)
+  * [[demonstrations:9_equipment:infrared_camera:start|Infrared camera]] (Optional)
 ===== Setup =====
-This apparatus can be plugged directly into the wall, but it is often more useful to vary the voltage (Using the variac, bottom of red closet). Place the nail in the holder and clamp so that the handles are held together by the nail and the screws. Increase the voltage so that the nail glows. By varying the voltage it is possible to see the nail glow red and then orange. When the nail is bright orange it will melt in half, causing the handles to spring apart. It is possible at this point to weld the nail back together so that it can be reused.
+This apparatus can be plugged directly into the wall, but it is often better to be able to vary the voltage. (In that case, plug the nail burner into the Variac, and the Variac into the wall.) Place the nail in the holder and clamp so that the handles are held together by the nail and the screws. Increase the voltage so that the nail glows. By varying the voltage it is possible to see the nail glow red and then orange. When the nail is bright white-orange it will melt in half, causing the handles to spring apart.
+At this point, as a 'bonus' demo, you can use the nail burner to weld the two halves of the nail back together. Simply press them together with the current turned on, and hold them together until the join between them glows bright white-orange. Then, turn off the power and let it cool a little bit before letting go.
 ===== Notes =====
+<WRAP center round important 60%>
+** Do not** use galvanized nails with this demonstration. [[wp>metal_fume_fever|Zinc fumes are highly toxic,]] use stainless steel nails for this.
+</WRAP>
-Even after the nail regains it's original colour it is still hot enough to burn you. Use the leather gloves.   Updated on: Jan 24, 2017
 <WRAP group>
@@ Line 60: / Line 53: @@
 </WRAP>
 <WRAP tablewidth 100%>
-| **Location** | ---- |
+| **Location** | P1 |
 | **Maker** | Unknown |
 | **Current State** | Working |