Question

Problem IIIA A pair of resistors RI and R2 share the wattage of W watts totally dissipated by them in the ccit of Figure. III-A a. Determine the currents I and I2 in terms of Ri, R. and W. (Ans: I(WR)2 x [R (RI+Ro)]A; Hint: Use current division theorenm b. Suppose Ri.30 and R23, denote the values of Ri and R respectively at room temperature 30 C. These elements are made of two different conducting materials of conductivities, Oj and σ2 된emery m (respectively) at room temperature (30 C); and, they are of identical geometry (of length L meter and cross sectional area A m). The temperature coefficients of resistivity of the heating elements, R1 and R2 are α/°C and α2 /°C respectively. Determine the values of the conductance, G, and Gz at 100 C. [Ans: G1-100-G-30 ( 1+7Ocri), unit ?; G2-100-1 c. In Fig. 3, the current (I) through Ri is set to control a current-controlled voltage- operated switch (trip-switch); and V Bl. Suppose the switch/trip operates when V,- V Determine the corresponding threshold temperature (Traabo in terms of tv Ylagbable β, σι, αι and A/L } , at which the switch will trip. FIGURE III-A R2 I2 Problem IV-A

Will leave a line for solving :)

Answer 1

and p are Pt22 0u

at 30 tip C. Cn 2-30 tharaers d- da

P1 EIA L VT