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Step of 7 1.002P (a) Value of resistance R is 1 Current flowing through 1 resistor is 20 mA Power (P) dissipated in the resistor is R = 0.4 W Power (P) dissipated in 1 kΩ resistor is 0.4 W For safe operation standard component having power rating greater than 0.4 W should be selected and hence 1/2 W or 1 W or2 W power rating components are used. Step of 7 (b) Value of resistance R is 1 Current flowing through resistor is 40 mA Power dissipated in the resistor is R =1.6 W Power (P) dissipated in 1 kΩ resistor is 1.6 W For safe operation standard component having power rating greater than 1.6 W should be selected and hence 2 W power rating components are used Step of 7 (c) Value of resistance R is 100 kΩ Current flowing through 100 kΩ resistor is 1 mA Power (P) dissipated in the resistor is R = 0.1 W Power P dissipated in 100 resistor is 0.1 W For safe operation standard component having power rating greater than 0.1 W should be selected and hence 1/8 W or W or 1/2 W Wor2 W power rating components are used Step of 7 (d) Value of resistance R is 10 Current flowing through 10 kΩ resistor is 4 mA Power (P) dissipated in the resistor is R = 0.16 W Power dissipated in 10 resistor is 0.16 W For safe operation standard component having power rating greater than 0.16 W should be selected and hence 1/4 W or 1/2 W Wor2 W power rating components are used Step of 7 (e) Value of resistance R is Voltage drop across the resistance is 20 V Power (P) dissipated in the resistor is R P= R = 0.4 W Power dissipated in 1 kΩ resistor is 0.4 W For safe operation standard component having power rating greater than 0.4 W should be selected and hence 1/2 W Wor2 W power rating components are used Step of 7 (f) Value of resistance R is Voltage drop across the resistance is 11 V Power dissipated in the resistor is R P R = = 0.121 W Step of 7 Power (P) dissipated in 1 resistor is 0.121 W For safe operation standard component having power rating greater than 0.121 W should be selected and hence 1/8 W or W or or 1/2 Wor2 W power rating components are used