R1 Vout a 17. Using the schematic to the right, design a variable voltage divider to provide output voltages ranging from a minimum of 40 V to a maxi- mum of 130 V. The maximum voltage must be at the maximum re- sistance setting of the potentiometer and the minimum voltage must be at the minimum resistance (zero ohms) setting of the potentiome- ter. When the minimum voltage is measured, the current should be 15 mA. What is the value of: R2 V1 150 V R1 = R3 R2 = R3= 18. E Va = -25 V (R6 V1 = R5 2.7kohm 4.7kohm V2 = F D V3 = Vs R4 1.2kohm It = AI R1 1.1kohm R3 2.2kohm R2 B 3.3kohm 19. Four 1/2 W resistors are in series: 50 2,7012, 100 2 and 120 2. To what maximum value can the current be raised before the power rating of one of the resistors is exceeded? Which resistor will burn out first? 20. A series circuit is made up of a 1/8 W resistor, a 1/4 W resistor, and a 1/2 W resistor. The total resistance is 1.8 k 2. If each resistor is operating at its maximum power level, determine the following: It = Vs= R1 = R2= R3=