A 40-W power transistor is to be cooled by attaching it to one of the commercially availab...

A 40-W power transistor is to be cooled by attaching it to one of the commercially available heat sinks shown in

FIGURE P3·–118

Table 3–6.Select a heat sink that will allow the case temperature ofthe transistor not toexceed 90°C inthe ambient airat20°e.