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--- 183_notes:examples:an_electric_heater [2014/10/28 04:40] – pwirving
+++ 183_notes:examples:an_electric_heater [2014/10/28 13:59] (current) – pwirving
@@ Line 16: / Line 16: @@
 === Approximations & Assumptions ===
+Assume no other energy transfers.
 === Representations ===
@@ Line 34: / Line 33: @@
  ${\Delta E_{thermal}} = {\Delta E_{sys}} = 0$
-This is a steady-state situation.
+This is a steady-state situation. This means that  $E_{sys}$  = 0 and W = 0.
  ${\Delta E_{sys}} = W + Q$  + electric energy input
+Therefore, 0 is equal to the amount of energy that flows from the surroundings into the system, due to a temperature difference between the system and surroundings plus other energy transfers.
  $0 = Q + 5000 J$
+Solve for Q
  $Q = -5000 J$