A transistor in a stereo amplifier dissipates 0.25 W within a cylindrical housing that has a radius of 8 mm and height of 8 mm. The top and sides are exposed to room air at 20 oC with a convection heat transfer coefficient h = 40 W/m2.K. Neglect the bottom. Find the transistor surface temperature

Which of the following components of a pid controlled accumulates the error over time and responds to system error after the error has been accumulated? a)- proportional b)- derivative c)- integral d)- on/off.

Ahot wire operates at a temperature of 200°c while the air temperature is 20°c. the hot wire element is a tungsten wire of 5 um diameter and 2 mm in length. plot using excel current, heat transfer and heat generated by the wire for air velocity varying from 1-10 m/s in steps of lm/s? matlab the sensor voltage output, resistance, or assume nu 0.989 re033pr13 take air properties at tr (200°c20°c)/2 = 110°c properties of tungsten: c 0.13 kj/kg.k 3 p 19250 kg/m k (thermal conductivity) = 174 w/m.k

The sum of the normal stresses does not change as the stress state rotates through an angle. a)-trune b)- false