The front door of a dishwasher of width 580 mm has a vertical air vent that is 500 mm in height with a 20-mm spacing between the inner tub operating at 52°C and an outer plate that is thermally insulated.
![383_0358a97b-9245-43f5-9d14-543a4b288f56.png](https://secure.tutorsglobe.com/CMSImages/383_0358a97b-9245-43f5-9d14-543a4b288f56.png)
(a) Determine the heat loss from the tub surface when the ambient air is 27°C.
(b) A change in the design of the door provides the opportunity to increase or decrease the 20-mm spacing by 10 mm. What recommendations would you offer with regard to how the change in spacing will alter heat losses?